Anchoring device and system for an intervertebral implant, intervertebral implant and implantation instrument

ABSTRACT

Anchoring devices, anchoring systems for intervertebral implants, intervertebral implants, and instruments and methods for implanting implants are disclosed. In preferred configurations, these various objects share the feature of comprising or cooperating with an anchoring device having a body comprising at least one curved plate elongated along a longitudinal axis, designed to be inserted through a passage crossing at least a part of implant, in order to penetrate into at least one vertebral endplate and attach implant onto this vertebral endplate by means of at least one stop retaining the implant, characterized in that the body comprises at least one longitudinal rib on at least a part of at least one of its faces, said rib being designed to cooperate with a groove made in passage of implant. In some preferred configurations, anchoring device comprises withdrawal stops or latches, and/or means for withdrawing the anchor from an inserted position.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/726,558 filed May 31, 2015, and issuing as U.S. Pat. No. 9,763,803 onSep. 19, 2017, which is a continuation of U.S. patent application Ser.No. 13/538,078 filed Jun. 29, 2012, and issuing as U.S. Pat. No.9,044,337 on Jun. 2, 2015, which is a continuation of InternationalApplication PCT/IB2009/008048 filed Dec. 31, 2009, and entering thenational stage in the United States on Jun. 29, 2012, as U.S. patentapplication Ser. No. 13/520,041. U.S. patent application Ser. No.13/538,078 is a U.S. national application under 35 U.S.C. § 111(a) filedduring the pendency of International Application PCT/IB2009/008048,which designates the United States, and U.S. patent application Ser. No.13/538,078 claims the benefit of the Dec. 31, 2009, filing date ofInternational Application PCT/IB2009/008048 under 35 U.S.C. § § 120 and365(c). International Application PCT/IB2009/008048 is incorporatedherein by reference.

BACKGROUND

The present invention concerns orthopedic implants, including spinalimplants such as intervertebral prostheses and intersomatic cages, forexample. Intervertebral prostheses may be implanted between two adjacentvertebrae to maintain or restore a space between the vertebrae whileconserving mobility of vertebrae. Intersomatic cages may be implantedbetween two adjacent vertebrae for placement and growth of bone tissuegrafts (or a substitute) in the disc space and to obtain an arthrodesis(the fusion of the two vertebrae). For example, after the cage ispositioned, the intervertebral space may be filled with autologousspongy bone or suitable bone substitutes, which may also (or in thealternative) be placed in a cavity in the cage, prior to its positioningin the intervertebral space. In particular, the invention concernsintervertebral implants, implant anchors, the fixation of implants tovertebrae by anchors, and implantation of implants in the disc space byan implantation instrument.

One problem in this field concerns the stability of spinal implants inthe disc space once they have been implanted, particularly when anarthrodesis is desired, for example using intersomatic cages or otherimplants allowing an arthrodesis. For example, there is a risk that theimplant will shift in the intervertebral space due to forces imposedwhen the patient moves, even when the implant is provided with notchesor teeth on its vertebral contact surfaces. Therefore it is oftennecessary to affix the spinal implant to the adjacent vertebrae betweenwhich it is implanted. Solutions are known in the prior art that providethe spinal implant with a bone anchoring device that allows solidlyattaching the implant into the vertebral endplates of the vertebraebetween which the implant is designed to be implanted. Moreover, accessto the intervertebral spaces (disc spaces) is often particularlydelicate due to the dimensions involved, particularly due to thepresence of blood vessels and nerves in the approach to theintervertebral space. Bone anchoring devices must penetrate into thevertebrae with sufficient depth to ensure a good fixation, and must alsohave a small size and allow affixing the implant without endangering thesurrounding blood vessels and nerves (for example, by not requiring morespace in the approach to the intervertebral space than necessary forimplantation of the spinal implant itself).

In the prior art, notably from published applications FR 2,916,956, US2009/105832, and WO 2008/149223 filed by the assignee of the presentapplication, which are incorporated herein by reference and to which thereader can refer to examine various problems resolved and variousadvantages provided by this type of solution, an anchoring device isknown, suitable to be implanted solidly and with sufficient depth in thevertebral endplates to ensure that the implant is held tight againstthese vertebrae, but along an axis of approach for insertion generallyin the plane of the intervertebral space. This type of solutiontypically comprises at least one anchor formed of a curved and rigidplate, arranged so as to penetrate into the endplate of a vertebrathrough an implant and provided with at least one stop to hold thisimplant against this vertebra. The rigidity of this type of anchor is animportant feature to allow effective fixation, notably more effectivethan staples or other thin and/or relatively flexible and often fragiledevices.

These types of anchoring devices (or “anchors”) comprising a curvedplate may pose a problem of the risk of splitting the vertebra duringthe impaction of the anchors into the vertebra, or due to forces imposedon the implant and/or the anchor once it is implanted in the vertebra.These types of anchors also may present a risk of making a cut that istoo large during the impaction of the anchors into the vertebra,allowing the possibility of undesirable play of the anchor, which makesthe implant fixation weak and/or unreliable. It should be noted that theterm impaction is used here to designate the fact that the anchoringdevice is driven into the vertebra. It will also be noted that thepresent application describes an impactor, which is a device forimpaction of the anchor because it is arranged to help driving ananchoring device into a vertebra.

Another potential problem of these types of anchors having a curvedplate concerns its rigidity. In some circumstances, it is important thatthe anchor is rigid enough that it will not deform and/or have much playunder the effects of the forces that are exerted on it, so that it willnot gradually come out of the vertebra in which it is embedded. Inaddition, passage of the anchor through the implant and maintenance ofthe stability of such anchor within the implant (subject to an eventualdesired play, for instance minimum play) is also an aspect that isimportant to ensure reliable mounting in some circumstances.

SUMMARY

Certain embodiments incorporating various technical features describedin the present application therefore aim to alleviate one or more ofthese and/or other disadvantages of the prior art by proposing ananchoring device for intervertebral implants that can be (more) compact(with lesser encumbrance) and (more) easily implantable, especiallyalong an axis substantially perpendicular to the axis of the spine, andthat can be rigid and allow (more) reliable fixation with reduced riskof damaging the vertebrae.

This goal is attained, for example, by a device for anchoringintervertebral implant in the vertebrae, comprising a body comprising atleast one curved plate elongated along a longitudinal axis extendingbetween a first end, called anterior, designed to penetrate into avertebra and a second end, called posterior, anchoring device beingdesigned to be inserted through a passage crossing at least a portion ofimplant, in order to penetrate into at least one vertebral endplate andaffix implant in this vertebral endplate by means of a stop retainingthe implant, characterized in that the body comprises at least onelongitudinal rib on at least a part of at least one of its faces, saidrib being designed to cooperate with at least one groove in passage ofimplant.

According to another feature, the height of said rib varies along thelongitudinal axis of body.

According to another feature, the height of said rib varies along thelongitudinal axis of body.

According to another feature, curved plate of the body describes atleast one arc of a circle or ellipse having dimensions and at least oneradius of curvature made in such a way that anchoring device can beimplanted in a vertebral endplate along an axis of approach forming anapproximately 90° with the vertical axis of the spine, while having itslongitudinal axis essentially in the plane of the intervertebral space.

According to another feature, the anterior end comprises at least onechamfer or at least one bevel facilitating penetration of device intothe vertebrae.

According to another feature, the anterior end comprises at least onenotch facilitating penetration of device into the vertebrae.

According to another feature, the body is provided with notches orientedso as to oppose the withdrawal of device once it is implanted in avertebra.

According to another feature, the body comprises at least one stop,called retaining, comprising at least one stop surface orientedessentially facing the anterior end, designed to cooperate with at leastone stop surface on implant that device is designed to affix, in orderto hold implant against the vertebra in which device is designed to beanchored.

According to another feature, the retaining stop comprises at least oneprojecting lug on at least one face of the body of anchoring device.

According to another feature, the retaining stop comprises twoprojecting lugs on the lateral sides of the body of anchoring device.

According to another feature, the retaining stop comprises two lugsprojecting perpendicularly to rib, at the level of the posterior end.

According to another feature, the body comprises at least one flexiblelug oriented toward the posterior end and forming a withdrawal stopopposing the withdrawal of anchoring device.

According to another feature, the curvature of plate is oriented in thedepth of plate.

According to another feature, the curvature of plate is oriented in thewidth of plate.

According to another feature, the anchoring device comprises, near theposterior end of plate, at least one portion of greater thickness thanthe thickness of the rest of plate, limiting the play of the device inpassage of implant.

According to another feature, the body comprises, near the posteriorend, at least one recess created to receive a tool to extract the deviceand allowing the withdrawal of the anchoring device.

According to another feature, the recess is open on the posterior end ofthe body, so that the tool can penetrate directly into said recess.

According to another feature, the stop end of flexible lug can bedisengaged from stop of the implant through a channel emerging outsideimplant.

According to another feature, the anchoring device comprises at leastone opening crossing plate to allow bone growth through device once itis implanted.

According to another feature, rib comprises a notch situated at adistance from the posterior end determined so this notch is stopped on astop surface at the end of passage of implant.

Another goal of various embodiments incorporating various technicalfeatures described in the present application is to alleviate one ormore of said (and/or other) disadvantages of the prior art by proposinga system of intervertebral anchoring that can be implanted substantiallyin the plane of the intervertebral space and that allows reliablefixation of the implant.

This goal is attained, for example, by a system for anchoringintervertebral implant in the vertebrae, characterized in that itcomprises two devices according to the invention, the first anchoringdevice comprising a stop called cooperation, comprising at least onestop surface oriented essentially facing the anterior end and the secondanchoring device comprising a stop, called cooperation, comprising atleast one stop surface oriented essentially in the direction facing theposterior end, these two cooperation stops being made so as to cooperatewith each other.

According to another feature, stop of the second anchoring devicecomprises a second stop surface, oriented essentially facing theanterior end, and the first device comprises a flexible lug positionedso that its posterior stop end comes into contact with the second stopsurface of stop then serving to support flexible lug, thus impeding thewithdrawal of the first device retaining the second device once it is inplace in implant.

According to another feature, the stop end of flexible lug of the firstdevice can be disengaged from the second stop surface of stop of thesecond device through a channel emerging outside the implant.

Another goal of certain embodiments incorporating various technicalfeatures described in the present application is to alleviate one ormore of said (and/or other) disadvantages of the prior art by proposingan intervertebral implant that can be implanted substantially in theplane of the intervertebral space, which can be attached solidly to thevertebrae by means of an anchoring device that can be implantedsubstantially in the plane of the intervertebral space.

This goal is attained, for example, by an Intervertebral implantcomprising at least one peripheral wall, at least a part of which,called posterior, comprises at least one straight passage of suitabledimensions to receive at least one anchoring device comprising a curvedplate, so as to allow the passage of this rigid anchoring device withoutdeformation despite its curvature, this passage crossing implant fromthe periphery toward an upper or lower surface, along a rectilinear andoblique trajectory adapted to the curvature of anchoring device,inserted essentially in the pane of implant, so as to orient anchoringdevice in the direction of the vertebral endplate of one of the vertebrabetween which implant is designed to be implanted, characterized in thatpassage comprises at least one groove designed to receive at least onerib of anchoring device according to the invention.

According to another feature, passage comprises at least one stopcomprising at least one stop surface oriented in the direction of theoutside of implant and designed to cooperate with at least one retainingstop of anchoring device so that this retaining stop retains implantonce anchoring device is anchored in a vertebra through passage.

According to another feature, the intervertebral implant comprises atleast one withdrawal stop comprising at least one stop surface orientedessentially facing the anterior end of the anchoring device inserted inpassage, this withdrawal stop cooperating with at least one flexible lugof anchoring device, in order to oppose the withdrawal of anchoringdevice from implant.

According to another feature, peripheral wall comprises at least onefastening means designed to cooperate with a gripping end of aninstrument for implanting implant.

According to another feature, the peripheral wall comprises two passageseach oriented toward one of the upper and lower surfaces of implant, soas to anchor anchoring device in each of the vertebrae between whichimplant is designed to be implanted.

According to another feature, the peripheral wall comprises, at aso-called anterior part, opposite the one comprising passage, at leastone beveled portion, so as to facilitate the insertion of implantbetween the vertebrae.

Another goal of certain embodiments incorporating various technicalfeatures described in the present application is to alleviate one ormore of said (and/or other) disadvantages of the prior art by proposingan instrument for implanting intervertebral implants between vertebraeand implanting an anchoring device in at least one of these vertebrae,which allows implanting the implants substantially in the plane of theintervertebral space and implanting an anchoring device along an axis ofapproach substantially in the plane of the intervertebral space.

This goal is attained, for example, by an instrumentation for implantingintervertebral implant between the vertebrae and implanting at least oneanchoring device in at least one of these vertebrae, the instrumentcomprising, on the one hand, at least one impactor comprising a head ofsuitable shape and size to press anchoring device and, on the otherhand, at least one guide of a shape elongated along a longitudinal axisextending between a first end, called gripping, of implant, and a secondend, called presser, the gripping end comprising at least one grippingmeans designed to cooperate with at least one fastening means ofimplant, characterized in that guide comprises a head of suitable shapeand size to receive head of the impactor at least partially andcomprising at least one guide surface having at least one radius ofcurvature essentially identical to at least one radius of curvature ofanchoring device according to the invention, so as to guide thisanchoring device through a passage of an implant according to theinvention, for compacting anchoring device in a vertebral endplate ofone of the vertebrae between which implant is designed to be implanted,head being made so as to allow the passage and/or guidance of rib ofanchoring device.

According to another feature, head comprises at least one groove madefor the passage of rib of anchoring device.

According to another feature, head of guide comprises a cavity ofsuitable shape and size to receive anchoring device and at leastpartially receive head of impactor, guide surface comprising at leasttwo curved grooves each situated on either side of this cavity to guidethe lateral sides of anchoring device on both sides of body, head ofimpactor penetrating into cavity from end to the other of these grooves.

According to another feature, shaft comprises a threaded end cooperatingwith a complementary threading of recess to affix implant when the shaftis activated by handle.

According to another feature, fastening means comprises a recess andthat gripping means comprises an end of a shaft sliding in a body ofguide when it is activated by a handle to enter and leave recess ofimplant.

According to another feature, fastening means comprise recess and agroove on a lateral side of peripheral wall, gripping means comprisingone end of a shaft sliding in a body of guide when it is activated by ahandle in order to enter and leave recess of implant and a lug made tobe engaged in groove and serving as a lever arm for positioning implant2) between the vertebrae.

According to another feature, groove comprises a recess designed toreceive a stud of lug so as to improve the grip of implant by theinstrument.

According to another feature, said groove created for passage of rib ofanchoring device is created on at least a part of the upper wall and/orthe lower wall of cavity of head of guide.

Other purposes of various embodiments incorporating various featuresdescribed in the present application are to overcome some drawbacks ofthe prior art and can be related to the problems mentioned above.

This purpose is reached, for example by a device for anchoringintervertebral implant in the vertebrae, comprising a body comprising atleast one straight plate elongated along a longitudinal axis extendingbetween a first end, called anterior, designed to penetrate into avertebra and a second end, called posterior, anchoring device beingdesigned to be inserted through a passage crossing at least a portion ofimplant, in order to penetrate into at least one vertebral endplate andaffix implant in this vertebral endplate by means of a stop retainingthe implant, characterized in that the body comprises at least onelongitudinal rib on at least a part of at least one of its faces, saidrib being designed to cooperate with at least one groove in the passageof implant

This purpose is reached, for example by a device for anchoringintervertebral implant in the vertebrae, comprising a body comprising atleast one plate elongated along a longitudinal axis extending between afirst end, called anterior, designed to penetrate into a vertebra and asecond end, called posterior, anchoring device being designed to beinserted through a passage crossing at least a portion of implant, inorder to penetrate into at least one vertebral endplate and affiximplant in this vertebral endplate by means of a stop retaining theimplant, characterized in that the body comprises at least one thickenedportion and/or at least one plane surface arranged for providing acontact with the inner wall of the passage in the implant and stabilizethe anchoring device in the implant.

This purpose is reached, for example by a device for anchoringintervertebral implant in the vertebrae, comprising a body comprising atleast one curved plate elongated along a longitudinal axis extendingbetween a first end, called anterior, designed to penetrate into avertebra and a second end, called posterior, anchoring device beingdesigned to be inserted through a passage crossing at least a portion ofimplant, in order to penetrate into at least one vertebral endplate andaffix implant in this vertebral endplate by means of a stop retainingthe implant, characterized in that the curvature of the plate isoriented along the width of the plate.

This purpose is reached, for example by a device for anchoringintervertebral implant in the vertebrae, comprising a body comprising atleast one plate elongated along a longitudinal axis extending between afirst end, called anterior, designed to penetrate into a vertebra and asecond end, called posterior, anchoring device being designed to beinserted through a passage crossing at least a portion of implant, inorder to penetrate into at least one vertebral endplate and affiximplant in this vertebral endplate by means of a stop retaining theimplant, characterized in that it comprises at least one withdrawal stopopposing to the withdrawal of the anchoring device from the implant bycontact with a complementary stop of the implant and comprises resourcesarranged for disengaging the withdrawal stop of the anchoring devicefrom its complementary stop.

This purpose is reached, for example by an Intervertebral implantcomprising at least one peripheral wall, at least a part of which,called posterior, comprises at least one passage of suitable dimensionsto receive at least one anchoring device comprising at least one plate,this passage crossing implant from the periphery toward an upper orlower surface, along a trajectory adapted to the anchoring device, so asto orient anchoring device in the direction of the vertebral endplate ofone of the vertebra between which implant is designed to be implanted,characterized in that the implant comprises at least one stopcomplementary to a withdrawal stop opposing to the withdrawal of theanchoring device from the implant and comprises resources arranged fordisengaging the withdrawal stop of the anchoring device from thecomplementary stop in the implant.

This purpose is reached, for example by an Intervertebral implantcomprising at least one peripheral wall, at least a part of which,called posterior, comprises at least one passage of suitable dimensionsto receive at least one anchoring device comprising at least one plate,this passage crossing implant from the periphery toward an upper orlower surface, along a trajectory adapted to the anchoring device, so asto orient anchoring device in the direction of the vertebral endplate ofone of the vertebra between which implant is designed to be implanted,characterized in that the implant comprises resources arranged for thewithdrawal of the anchoring device.

This purpose is reached, for example by a system for anchoringintervertebral implant in the vertebrae, characterized in that itcomprises two anchoring devices for anchoring an implant in vertebrae,each device having a body comprising at least one plate elongated alonga longitudinal axis extending between a first end, called anterior,being designed to penetrate into a vertebra and a second end, calledposterior, the anchoring devices being designed being designed to beinserted through a passage crossing at least a portion of implant, inorder to penetrate into at least one vertebral endplate and affiximplant in this vertebral endplate by means of a stop retaining theimplant, characterized in that the first anchoring device comprising astop called cooperation, comprising at least one stop surface orientedessentially facing the anterior end and the second anchoring devicecomprising a stop, called cooperation, comprising at least one stopsurface oriented essentially in the direction facing the posterior end,these two cooperation stops being made so as to cooperate with eachother.

According to another feature of the anchoring system, stop of the secondanchoring device comprises a second stop surface, oriented essentiallyfacing the anterior end, and the first device comprises a withdrawalstop positioned so that its posterior stop end comes into contact withthe second stop surface of stop then serving to support the withdrawalstop, thus impeding the withdrawal of the first device retaining thesecond device once it is in place in implant.

According to another feature of the anchoring system, at least one ofthe anchoring device comprises resources arranged for disengaging thewithdrawal stop from the second stop surface.

This purpose is reached, for example by an Intervertebral implantcomprising at least one peripheral wall, at least a part of which,called posterior, comprises at least two passages of suitable dimensionsto receive at least two anchoring devices of a system according to theinvention, these passages crossing implant from the periphery toward anupper or lower surface, along a trajectory adapted to the anchoringdevice, so as to orient anchoring device in the direction of thevertebral endplate of one of the vertebra between which implant isdesigned to be implanted, characterized in that the implant comprisesresources arranged for the withdrawal of the anchoring device via thecooperation stops.

This purpose is reached, for example by an Intervertebral implantcomprising at least one peripheral wall, at least a part of which,called posterior, comprises at least two passages of suitable dimensionsto receive at least two anchoring devices of a system according to theinvention, these passages crossing implant from the periphery toward anupper or lower surface, along a trajectory adapted to the anchoringdevice, so as to orient anchoring device in the direction of thevertebral endplate of one of the vertebra between which implant isdesigned to be implanted, characterized in that the implant comprisesresources arranged for disengaging the withdrawal stop of the anchoringdevice.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

Other features and advantages of various embodiments of the presentinvention will appear more clearly upon reading the description below,made in reference to the attached drawings, in which:

FIG. 1 shows a perspective view of an intervertebral implant providedwith two anchoring devices according to one of various embodiments ofthe invention.

FIGS. 2A, 2B, and 2D respectively show a perspective view from thefront, a sectional view along plane 2B-2B of FIG. 2A, and a perspectiveview from the rear, of one of various embodiments of an intervertebralimplant alone, FIGS. 2C, 2E, and 2F respectively show a perspective viewfrom the rear, a top view, and a sectional view along plane 2F-2F ofFIG. 2E, of the same implant provided with two anchoring devices, andFIGS. 2G and 2H show two of various embodiments of anchoring devicesthat can be used with the implants of FIGS. 2A to 2F.

FIGS. 3B, 3E, 3H, and 3K show rear views of four of various embodimentsof intervertebral implants and the cutting planes for associatedsectional views, FIGS. 3A and 3C show sectional views of the implant ofFIG. 3B, FIGS. 3D and 3F show sectional views of the implant of FIG. 3E,FIGS. 3G and 3I show sectional views of the implant of FIG. 3H, andFIGS. 3J and 3L show sectional views of the implant of FIG. 3K.

FIGS. 4A, 4B, 4C, 4D, 4E, 4F, 4G, and 4H show rear views of 8 of thevarious embodiments of an intervertebral implant, revealing the profilesof several of various embodiments of anchoring devices that may be usedto secure them to vertebrae.

FIGS. 5A, 5B, and 5C show perspective views of 3 of various embodimentsof an intervertebral implant, FIG. 5D shows a top view of the implant ofFIG. 5C provided with two anchoring devices such as those shown inperspective in FIG. 5F, and FIG. 5E shows a sectional view of thisimplant and the anchors along plane 5E-5E of FIG. 5D,

FIGS. 6A, 6B, 6C, 6D, 6E, 6F, and 6G show, respectively, 3 sectionalviews and 4 perspective views of 7 of various embodiments of ananchoring device.

FIGS. 7A and 7B show perspective views of one of various embodiments ofan implant, respectively alone and provided with a pair of anchoringdevices like those shown in perspective in FIG. 7E, and FIGS. 7C and 7Drespectively show a top view and a sectional view along plane 7D-7D ofFIG. 7C, of the implant of FIG. 7B provided with these anchoringdevices.

FIGS. 8A, 8B, and 8C show rear views of 3 of various intervertebralimplant embodiments designed to receive anchoring devices like thoseshown in perspective, respectively, in FIGS. 8D, 8E, and 8F, and FIGS.8G and 8H respectively show a top view and a sectional view along plane8H-8H of FIG. 8G, of any of the implants of FIGS. 8A, 8B and 8C providedwith any of the anchoring devices of FIGS. 8D, 8E, and 8F.

FIGS. 9A, 9B, and 9C show perspective views of pairs of anchoringdevices according to 3 of various embodiments, FIGS. 9D and 9E show topviews of various implants designed to receive devices such as those,respectively, of FIGS. 9A and 9C, and FIGS. 9F and 9G show sectionalviews along planes 9F-9F and 9G-9G, respectively, of the implants andanchors of FIGS. 9D and 9E, respectively.

FIGS. 10A, 10B, and 10C show perspective views of pairs of anchoringdevices according to 3 of various embodiments, FIGS. 10D, 10E, and 10Fshow top views of the implants receiving devices such as those,respectively, of FIGS. 10A, 10B, and 10C, and FIGS. 10G, 10H, and 10Ishow sectional views along planes 10G-10G, 10H-10H, and 10I-10Irespectively, of the implants of FIGS. 10D, 10E, and 10F, respectively.

FIGS. 11A and 11B show perspective views of pairs of anchoring devicesaccording to 2 of various embodiments, FIGS. 11C and 11D show top views,and FIGS. 11E and 11F show sectional views along planes 11E-11E and11F-11F, respectively, of implants deployed with the anchors of FIGS.11A and 11B, respectively.

FIGS. 12A and 12B show, respectively, a top view and a sectional viewalong plane 12B-12B of FIG. 12A of various embodiments of anintervertebral implant provided with a pair of one of variousembodiments of anchoring devices, and FIGS. 12C, 12D, and 12E show,respectively, a front view, a perspective view, and a sectional viewalong plane 12E-12E of FIG. 12C of this pair of anchoring devices in adeployed configuration.

FIGS. 13A, 13B, and 13C show, respectively, a perspective view, a topview and a sectional view along plane 13C-13C of FIG. 13B, of one ofvarious embodiments of the implant alone, and FIGS. 13D, 13E, and 13Fshow, respectively, a perspective view, a top view, and a sectional viewalong plane 13F-13F of FIG. 13E of this implant provided with a pair ofanchoring devices such as the particular embodiment shown in perspectivein FIG. 13G,

FIGS. 14A and 14B show top views of one of various embodiments of ananchoring device comprising flexible lateral lugs that are,respectively, unfolded and folded, FIGS. 14C, 14D, and 14E show,respectively, a profile view, a rear perspective view, and a frontperspective view of one of various embodiments of an anchoring devicecomprising a rib on its concave face, and FIGS. 14F, 14G, and 14H show,respectively, a profile view, a rear perspective view, and a frontperspective view of an embodiment of one of various embodiments ofanchoring devices comprising a rib on each of its faces.

FIGS. 15A, 15B, 15C, and 15D show, respectively, a top view, a sectionalview along plane 15B-15B of FIG. 15A, a sectional view along plane15C-15C of FIG. 15A, and a sectional view along plane 15D-15D of FIG.15A, of one of various embodiments of intervertebral implants alone,FIG. 15E shows a profile view of this implant, and FIG. 15F shows asectional view along plane 15F-15F of FIG. 15E of this implant,revealing the shape of a passage in the implant for an anchoring device.

FIGS. 16A, 16B, and 16C show, respectively, a profile view, a sectionalview along plane 16B-16B of FIG. 16A, and a top view of one of variousembodiments of an instrument comprising an impactor and a guide, withone of various embodiments of an implant shown attached in FIGS. 16A and16B.

FIGS. 17A, 17B, 17C, 17D, and 17E show partial views of the gripping endof one of various combinations of embodiments, showing respectively atop view of a guide approaching an implant, a top view of a guideholding an implant, a top view of a guide holding an implant providedwith a pair of anchoring devices, a sectional view along plane 17D-17Dof FIG. 17C of the guide holding the implant provided with a pair ofanchoring devices (one shown in place and the other shown inside theguide, about to be implanted), and a perspective of the guide holding animplant provided with a pair of anchoring devices.

FIGS. 18A and 18B are perspective views, respectively from above andbelow, of one of various embodiments of an anchoring device, FIGS. 18Cand 18D respectively represent a top view and section view along theplane 18D-18D of FIG. 18C of one of various embodiments of an implantfitted with such anchoring devices, and FIGS. 18E and 18F representrespectively a top view and a sectional view along the plane 18F-18F ofFIG. 18E, of this implant without the anchoring devices in place.

FIG. 19A is a top view of one of various embodiments of an implant,FIGS. 19B and 19C, respectively, showing a side view and front view ofone of various embodiments of a scoliosing and lordosing implant, FIG.19D showing a rear view of an embodiment of a lordosing implant, FIGS.19E and 19G each showing a rear view of two of various embodiments ofnon-lordosing implants, and FIGS. 19F and 19H each showing a view of twoof various embodiments of scoliosing implants.

FIG. 20A shows a perspective view of one of various embodiments of anadapter and FIG. 20B shows a side view of one of various embodiments ofan impactor penetrating in an adapter holding an anchor.

DETAILED DESCRIPTIONS

Various embodiments of the invention will now be described in referenceto the figures of the present application. The invention simultaneouslyconcerns three groups of objects:

anchoring devices (1) (or “anchors”), and/or anchoring systemscomprising plural anchoring devices (1) that may be identical,different, or complementary;

intervertebral implants (2) configured for receiving one or more of suchanchoring devices (1) or systems; and

instruments (3, 4) for implanting implants (2) between the vertebrae andfixing implants with one or more anchoring devices (1) or anchoringsystems.

Each group of objects may comprise various possible embodiments,relating to a given object. Each object comprises various elements(generally constituent of the object) characterized by at least onetechnical feature. Each object (of a given group) concerned by at leastone technical feature might be associated with at least one other object(of the same or another group), for example with respect to at least onecomplementary technical feature, such that the groups of objects share acommon inventive concept. The invention may thus also concern anensemble comprising at least two of these objects, as well as eachobject individually. The elements (for example a plate, a lug, a stop, araised portion, etc.) and their technical features (for example acurvature, a flexibility, a possible disengagement, a height, a stopsurface, etc.) are described in more detail hereafter in the presentapplication. At least one technical feature corresponding to an elementof a given object solves at least one technical problem, in particularamong those mentioned in the preamble of the present application. Thepresent application thus describes various embodiments andconfigurations for each object or group of objects, by specifying atleast one technical feature of at least one element. It will beunderstood from reading the present application that the varioustechnical features of each element described in at least one embodimentor configuration may be isolated from other technical features of theobject concerned by (or the objects concerned by and/or associated with)said embodiment or configuration (and thus concerning the same oranother element) and/or may be combined with any other technical featuredescribed herein, in various embodiments or configurations, unlessexplicitly stated otherwise, or unless these features are incompatibleand/or their combination is not functional, in particular because thestructural adaptations that may be required by such isolation orcombination of features are directly derivable from the appreciation ofthe present disclosure. Similarly, although some technical features arediscussed herein in reference to the anchor device, they may beincorporated in various embodiments of the anchoring systems. Generallyspeaking, the specific technical feature(s) concerning a given elementshouldn't be considered as exclusive from those concerning anotherelement, nor from other technical features concerning the same element,except if it clearly appears that the combination of these technicalfeatures is impossible or nonfunctional. Although the presentapplication details various embodiments or configurations of theinvention (including preferred embodiments), its spirit and scopeshouldn't be restricted to the examples given.

Various embodiments of anchoring devices (1) in accordance with thepresent invention are usable with intervertebral implants (2), such as,for example, intersomatic cages or intervertebral disc prostheses.Intervertebral implants are designed to be implanted between twoadjacent vertebrae of the vertebral column (spine) or to provide ajunction between two vertebrae, at their periphery in the case ofosteosynthesis plates (which can be used alone or in combination with anintersomatic cage). Anchoring device (1) is designed to be anchored inone of the vertebrae so as to attach the implant to this vertebra.Various embodiments of anchoring devices (1) according to the inventioncomprise at least one curved and rigid plate, configured for penetrationinto a vertebra through an implant and comprise at least one stop tohold this implant against this vertebra. The technical features of“curvature” and “rigidity” concerning the “plate” element of the“anchor” object are described in detail below. Device (1) for anchoringintervertebral implant (2) in the vertebrae will also be referred to inthe present application by the term “anchor” (1), without introducingany limitation whatsoever. This type of anchor has been described inpublications FR 2,916,956, US 2009/105832 and WO 2008/149223 ofapplications filed by the assignee of the present application, hereinincorporated by reference in their entirety. In various embodiments,anchor (1) comprises a body including at least one curved plate (10)elongated along a longitudinal axis (L, FIGS. 13E and 14A). Thislongitudinal axis (L) of anchor (1) extends between a first end, whichwill be referred to as the anterior end, designed to penetrate into avertebra, and a second end, which will be referred to as the posteriorend. Note that the designations of the “posterior” and “anterior” endsof anchor (1), implant (2), and instrument (3, 4) are used in thepresent application in reference to the direction in which anchor (1)will be inserted. Thus for anchor (1), the first end (referred to as theanterior end) is the one designed to be inserted first and designed topenetrate into a vertebra to affix an implant. Concerning the implant,its wall or end denoted as “posterior” is the one comprising an openingof a passage for the insertion of the anchor, whether this wall isreally posterior to the implant or not during deployment. Concerning theinstrument, the anterior end is the one intended to be abutted on theimplant for the insertion of the anchor within the passage. Certainembodiments of implants (2), including some described in detail in thisdisclosure and concerning an intersomatic cage, are made for lateralinsertion into the disc space, and accordingly the posterior end will bepositioned on a lateral side of the vertebrae, while the anterior endwill be positioned near the medial line or on the opposite lateralslide. Nevertheless, the terms “anterior” and “posterior” will still beused since they are easier to understand from the point of view ofimplantation and may be commonly and conveniently used with reference toanchor (1), implant (2), and instrument (3, 4) regardless of theimplantation approach (implantation path) chosen. Accordingly, the terms“anterior” and posterior” are not intended to refer simply with respectto a patient or an anatomical feature of a patient. It will be noted aswell that reference is made herein to a longitudinal axis (L) betweenthese two ends and that this longitudinal axis (L) therefore correspondsto a anteroposterior axis of anchor (1), implant (2), and instrument (3,4), still in reference to the direction of insertion of the anchor (1).It will also be noted that the term “substantially” is used severaltimes in the present description, in particular concerning a technicalfeature such as an orientation or a direction, so as to indicate thatthe feature concerned may in fact be slightly different and not exactlyas stated (for example, the expression “substantially perpendicular”should be interpreted as “at least approximately perpendicular” becauseit may be possible to choose an orientation which is not exactlyperpendicular for allowing however to serve substantially the samefunction). Furthermore, the term “substantially” used in the presentapplication may also be interpreted as defining that the technicalfeature may “in general” (“generally”), and often “preferably”, asstated, but that other embodiments or configurations may be within thescope of the present invention.

The fact that anchor (1) may comprise at least one plate (10) allowsanchor (1) to ensure a good hold, at least in a direction substantiallyperpendicular to the plate, since the width of the plate offers asurface opposing movement of the anchor and thus of the implant(perpendicularly to this surface) in the bone tissue in which it isimplanted. It will be noted that when the plate is curved, this hold iscreated along at least one direction substantially radial to the radiusof curvature of the plate. In fact, various embodiments of the presentinvention, like various embodiments of the one described in theapplications cited above, have the advantage of a having curvature thatallows it to be implanted in the vertebral endplate of a vertebra alongan approach axis substantially perpendicular to the axis of the spine atthe level of the vertebrae between which the implant is implanted (or inthe plane of the intervertebral space), which may facilitateimplantation and allow avoiding some of the disadvantages linked to theencumbrance (dimensions) of the approach to the vertebrae. On the otherhand, in various embodiments the anchor advantageously has the shape ofa plate which may be relatively thin, facilitating the penetration ofanchor (1) into the bone tissue. This thinness of plate (10) may pose aproblem of stability of anchor (1) in the vertebra, to the extent thatthe plate might form a sort of blade that can split the vertebra in adirection along the width of the plate (transversely to longitudinalaxis (L) of various embodiments), notably during its impaction in thevertebra, or later, due to the significant stress applied thereon whenthe patient moves, for example. Furthermore, this thinness may diminishthe rigidity of the plate. In some applications rigidity may be animportant feature for effective fixation, resulting in embodimentsparticularly more effective than staples or other thin and/or relativelyflexible, often fragile, devices, which do not allow a good hold due totheir flexibility and/or thinness and/or their fragility. Therefore,rigid anchors are preferred for many embodiments (curved anchors beingalso preferred, but for facilitating the approach to vertebrae), insteadof deformable anchors. Rigid anchors penetrate into the vertebraethrough a passage (21) crossing at least a part of the implant withoutbeing deformed in this passage (21). For these rigid embodiments, innerwalls (210) of this passage (21) in the implant preferably have shapesand dimensions that allow the anchor to pass: either by a curvaturecomplementary to that of the anchor, or by an uncurved shape with aheight slightly greater than that of the anchor to permit its passagedespite its curvature and rigidity (thus avoiding machining a curvedpassage in the implant, which may be complex and costly).

Various embodiments of the present invention resolve problems ofstability and rigidity of anchor (1) by using at least one longitudinalrib (11) over at least one part of at least one of the faces of the bodyof anchor (1). This longitudinal rib (11) preferably is orientated inthe direction of the length of plate (10), substantially parallel tolongitudinal axis (L) in various embodiments. Note that the presentinvention foresees various configurations of anchor (1) with regard tothe direction of its curvature. By referring again to the direction ofinsertion of the anchor, it is understood that various embodiments ofthe anchor are designed to penetrate from the periphery of the discspace into the vertebrae, preferably into the inferior vertebralendplate of the upper vertebra or into the superior vertebral endplateof the lower vertebra, in particular in the case of implants such asintersomatic cages or intervertebral disc prosthesis. Also, otherembodiments of the anchor may be configured for implantation preferablyinto the periphery of the vertebral body near the intervertebral space,especially in the case of intervertebral implants such as osteosynthesisplates. When an anchor is intended for implantation into the vertebralplate, for example through implants such as intersomatic cages orintervertebral disc prosthesis, the curvature of the anchor ispreferably configured so that, once embedded in a vertebra, the axis ofthe spine is substantially tangential to a substantial part of itsanterior extremity, or at least that this part of the anterior end formsa small (or slight) angle with the vertical axis of the spine.

The invention also foresees various embodiments of anchors (and thusalso of the implants and instruments that may be associated therewith)in which the width of the plate (10) of anchor (1) is orientedsubstantially along this vertical axis of the spine and otherembodiments of anchors (and thus also of the implants and instrumentsthat may be associated therewith) in which the width of the plate (10)of anchor (1) is oriented substantially perpendicularly to this verticalaxis of the spine, i.e., generally horizontally. Thus, in certainembodiments, the curvature of plate (10) of anchor (1) may be orientedin the width of plate (10), as shown, in particular, in FIGS. 13D-13Gand as indicated by FIGS. 3B, 3K, 4A, and 13A-C. These particularembodiments of the anchor preferably, in particular in the case ofimplants intended for implantation through an anterior anatomic pathway,include at least one rib (11), which allows stabilizing the anchoringdevice and helps prevent it from damaging the vertebrae too much. In theabsence of such a rib, it would not be preferable to orientate thecurvature in this direction, because the implants implanted through ananterior anatomical path (substantially sagittal or para-sagittal), willbe affixed by an anchor along this same direction while the strongestconstraints that are exerted on the implants are oriented in this samedirection (sagittal or para-sagittal). Conversely, for implants (such ascages or implants, for example) intended for implantation by a lateralpath to have, this curvature oriented along the width of the plate (10)of anchor (1) is preferable and may not need a rib (11) because theplane of the plate is configured to be substantially perpendicular tothe sagittal axis (or para-sagittal) of the spine and therefore opposedto the strongest constraints exerted on the implant and anchor. It willthus be understood that particularly when the plane of the plate isconfigured to be substantially perpendicular to the axis along which thestrongest constraints are exerted, depending on the anatomicalimplantation's pathway, it is possible not to have rib (11) on theanchor (1), nor corresponding grooves (211, 3011) in associated implantsand instruments. Thus, the present application foresees variousembodiments of anchors (1) comprising no rib (11), particularly forconfigurations in which the curvature of the anchor (1) is configured asa function of the anatomical implantation path so that the plate (10)can ideally oppose to the strongest constraints when the implant andanchor are in place in the patient, and in particular anchors (1) curvedalong the width of the plate for implants with a lateral anatomicimplantation path. The implants and instruments that may be associatedwith such anchors need not comprise grooves (211, 3011). Theseparticular objects may or may not also include any technical feature (orcombination of technical features) described for any element (orcombination of elements) of any object (or combination of objects)disclosed in this application, as long as they are not incompatible, inparticular because the structural adaptations that may be required bysuch isolation or combination of features are directly derivable fromthe appreciation of the present disclosure. Note that the curvature ofthe anchor along the width of the plate (10) allows referring to twolateral faces, and to a concave side (or edge) (inside the curve) and aconvex side (or edge) (outside the curve) of anchor (1).

In other embodiments of anchors (and thus also of the implants andinstruments that may be associated therewith), for example, as shown byFIGS. 2G and 2H, the curvature of plate (10) is oriented in the depth(or height, thickness) of the plate. Note that the curvature of theanchor in this orientation allows referring to a concave face (insidethe curve) and a convex face (outside the curve) of anchor (1), as wellas two lateral sides (or edges) of the anchor (1). Note that theinvention also foresees combinations of various objects described in thepresent application, by the incorporation of various technical featuresof anchors (1) and/or implants (2) and/or instruments (3, 4). Forexample, FIG. 3E shows a “mixed” implant (2) provided with two types ofpassages (21) each designed to receive an anchor having a differentcurvature orientation. Note also that longitudinal axis (L) is shown fordifferent variants of curvature in FIGS. 13E and 14A.

It will be noted also that the invention foresees various embodiments ofanchors (and thus also of the implants and instruments that may beassociated therewith) with regard to the position and length of rib(11). Generally, rib (11) preferably is designed at least to inhibit (orprevent) the anchor (1) (and thus also the implant) from movingtransversely with respect to the vertebra. The rib (11) may also beconfigured and deployed to improve the rigidity of the anchor (1). Thusit is generally preferable for the rib to be present on a part of anchor(1) that extends outside the implant (2) when fully inserted therein.The rib can, but need not, extend up to the anterior end, and thus canstop nearby or at a given distance from this anterior end. Also, it isnot generally necessary that the rib extend up to or near the posteriorend that is designed to remain in the implant. When the rib extends upto or near the posterior end, however, it may allow furtherstabilization of the anchor in the implant (for example, by means of itscooperation with groove (211) in the passage). Although variouspreferred embodiments of the anchor have at least one rib (11) on atleast one part of at least one of the faces of anchor (1), the inventionforesees numerous other embodiments, of which some of the diverseexamples are shown in the figures and/or discussed elsewhere herein. Inthe majority of figures showing anchors whose curvature is oriented inthe direction of the depth of plate (10), the rib is positioned on theconvex face (see, for example, FIGS. 2G and 2H). However, in certainembodiments, at least one rib (11) may be provided on the concave faceas shown, for example, in FIGS. 14C, 14D, and 14E. In other embodiments,at least one rib may be provided on each of the faces of the anchor, asshown, for example, in FIGS. 14F, 14G, and 14H. Likewise, variousillustrative and non-limiting examples of implants (2) designed toreceive various types of anchors (1) are shown, for example, in FIGS.3(A to L) and FIGS. 4(A to H). These figures show the profile that theentrance to the passage has, and the preferable rib configuration of theanchor that will be associated with it. In addition, FIGS. 3A, 3C, 3D,3F, 3G, 3I, 3J, and 3L show sectional views of implants showing theshape of passages (21) in the implants, which generally will be afunction of the types of anchors preferably used with those implants.For example, FIG. 3B shows an implant (2) with which 2 anchors (1) willbe associated, each anchor having a vertical orientation (anchor curvedin the direction of the plate width), while FIG. 3E shows a “mixed”implant (2) with which 1 anchor (1) with vertical orientation and 1anchor with horizontal orientation (anchor curved in the direction ofthe plate depth) will be associated. FIG. 3H shows an implant (2) withwhich 2 anchors (1) will be associated with horizontal orientation witheach having a rib (11) on the convex face, and FIG. 3K shows an implant(2) with which 2 anchors (1) will be associated with verticalorientation, with each having a rib situated on a lateral face towardthe inside of the implant. FIG. 4A shows an implant (2) with which 2anchors (1) will be associated with vertical orientation, with eachhaving a rib (11) on a lateral face toward the outside of the implant.As discussed elsewhere in this disclosure, anchors (1) which will beassociated with the implants of FIGS. 4A and 4E will comprise aretaining stop (14) on the face opposite the one with the rib (11), saidretaining stop (14) being arranged for cooperating with a stop (214) ofthe implant shown on these figures. FIGS. 4B and 4C each show an implant(2) with which 2 anchors (1) will be associated, each anchor (1) havinga horizontal orientation and 2 ribs (11) on the convex face (somewhatoffset toward the lateral sides from one figure to the other). FIG. 4Dshows an implant (2) with which 2 anchors (1) will be associated, eachanchor (1) having horizontal orientation and a single rib (11) on theconvex face (central for FIG. 4D and off-center for FIG. 4E). FIGS. 4Eand 4F each shows an implant (2) with which 2 anchors (1) will beassociated with horizontal orientation, one of which will have a singlerib (11) on the convex face while the other will have a single rib (11)on the concave face (a central ribs for FIG. 4F and offset ribs for FIG.4E). FIG. 4G shows an implant (2) with which 2 anchors (1) will beassociated, each anchor (1) having horizontal orientation and a singlerib (11) centered on the concave face. FIG. 4H shows an implant (2) withwhich 2 anchors (1) will be associated, each anchor having a horizontalorientation and two ribs (11) on the concave face. Anchors (1) withoff-center ribs (such as the ones shown, for example, in FIG. 5F) permitreducing the size required for the presence of two passages (21) inimplants (2), as is especially visible in the examples of FIGS. 5A, 5B,and 5C. In various embodiments of implants, the use of off-center ribsavoids having 2 aligned grooves (211) such as shown in FIG. 4D, whichcould make the implant fragile, and may thus allow either havingintersomatic cages with a relatively small height if the configurationof the spine requires it, or keeping more material above (and/or below)the passage to provide a stronger implant or arranging a centralattachment (22) resource (possibly larger than in other configurations)as particularly visible on FIG. 5A. These illustrative and non-limitingexamples demonstrate that the various objects of the invention are notlimited regarding the number or positions of the anchors, nor the numberor positions of their rib(s), although certain configurations areparticularly advantageous, notably in terms of resistance or size of theimplant (for example, in the case of the cervical implant, where thesmall size places strong constraints on the size and where the strengthof the materials requires that the implants not be made excessivelyfragile by passages (21), especially in the case of intersomatic cagesmade of PEEK (polyether ether ketone).

In various anchor and anchor system embodiments of the invention, plate(10) can be substantially rectangular, as is shown in many of thefigures, but can, of course, have various other shapes without departingfrom the spirit of the invention. Preferably, whatever the shape of theperiphery of the plate, it presents at least one surface of sufficientdimension for efficiently opposing its movements in the vertebra,contrarily to staples, nails or other known devices. For example, mostof the plates shown in the figures have a substantially rectangularperiphery, but have variations in shape described in detail in thepresent application. Moreover, anchor (1) can comprise several plates,and/or a single plate of the body can have various shapes withoutdeparting from the spirit of the invention. In fact, to the extent thatthe desired hold can be obtained by at least one plate offering at leastone surface sufficient in the dimension described here as the width ofthe plate, the anchor can comprise plates having a substantiallytrapezoidal or triangular periphery or having diverse shape variations.For example, in certain variants of anchor (1) (not shown), the body ofanchoring device (1) may have two plates substantially parallel to oneanother (and/or with substantially the same curvature) and connectedtogether at the posterior end, for example, such as described inpublications FR 2,827,156 (and WO 03/005939 and US 2004/0199254) and FR2,879,436 (and WO 2006/120505 and US 2006/0136063), each of which isincorporated herein by reference, which may form a stop holding anchor(1) on the implant and thus holding the implant against the vertebra. Inaddition, as discussed elsewhere in this disclosure, various embodimentsof anchors (1) may comprise at least one straight plate, for examplesuch as described in these publications, or comprise 2 straight platesconnected by a link able to, or arranged to, form a stop allowing toaffix the implant. Generally, various anchor embodiments of theinvention may use a rib (11) to provide a good hold perpendicular to thewidth of the plate, and such a rib may, in fact, be formed by at leastone fin or at least one similar structure (or several structures), toimprove the rigidity of the anchor and offer a surface opposingtransverse movement of the anchor in the bone tissue. Variousembodiments of anchors are also foreseen with respect to the technicalfeatures of the dimensions, in particular the height, of the rib, whichis preferably arranged for opposing to this transverse movement. Theheight of the rib (11) may for example be approximately half of thewidth of the plate (10) of anchor (1), so as to form itself a secondplate particularly efficient in its stabilizing function.

Various embodiments of the invention strive to reduce the size of thedevices and associated instruments, so as to allow implanting theanchoring device along an axis substantially in the plane of theintervertebral space (disc space). As described in publications ofapplications FR 2,916,956, US 2009/105832, and WO 2008/149223 citedabove and incorporated herein by reference, curved plate (10) describes,along the longitudinal axis, at least one arc of a circle and/or atleast one arc of an ellipse whose dimensions and radii of curvature arecreated so that anchoring device (1) can be implanted in the vertebralendplate of a vertebra by having its perpendicular axis substantially inthe plane of the intervertebral space, i.e., along an axis of approachsubstantially perpendicular to the axis of the spine (i.e., said planeor said approach axis being substantially tangential to at least part ofthe anterior end when the anchor approaches the vertebrae). Similarly tothe above cited applications, various embodiments of the various objectsof the present invention concern the technical feature of the radius (orradii) of curvature of anchoring device (1). Various embodiments ofanchoring device (1) in fact have a different radius of curvature fromone anchor to another, and/or several different radii of curvature ondifferent portions of the body of a given anchor (1). Thus, for example,the body of anchor (1) may have an arc of a circle or arc of an ellipseshape, but it may also describe a more complex curvature, as if severalarc(s) of a circle, having a same radius of curvature or different radiiof curvature, were placed end to end or if several arc(s) of an ellipse,having a same radius of curvature or different radii of curvature, wereplaced end to end, or any combination of arcs of a circle or ellipse oreven a radius of curvature that varies along the body. In the presentdescription, the terms “arc of a circle” or “radius of curvature”encompass all these different possibilities. Thus, various embodimentsof the present invention provide different variants concerning theradius of curvature and certain related aspects of anchoring device (1),as well as implants (2) and instruments (3, 4) that may be associatedwith it. In fact, for example, depending on the use of device (1) and inparticular its intended implantation location along the spine, it may bepreferable to have a larger or smaller radius of curvature. Depending onthe radius of curvature of anchoring device (1), the axes passing,respectively, through the penetration end and the stop end of device (1)form an angle, typically comprised between approximately 90° and 180°,although it may also be chosen to be less than 90°. Preferably, thisangle will be comprised between 110° and 160°, which, in manycircumstances, will facilitate implanting the device better than anangle outside these values. According to the fixation that one wishes toobtain by means of anchoring device (1), the angle will be selected tobe more or less open. If one wishes, for example, to promote tightaffixation of the cage or the prosthesis against the vertebral endplate,an angle comprised between 120° and 180° may be preferred, while if onewishes rather to prevent the implant from moving in the plane of thedisc space, an angle comprised between 90° and 150° may be preferred.Although these angle variations are not shown in the figures, differentangles for anchoring device (1) permit covering the different desirabletypes of anchoring in order to assure a fixation of the implants that isadapted to the case. A device (1) whose angle is at an optimal value,for example near 135°, can also be provided in one of the preferredembodiments for fixation of the device both by pressing the implanttight against the vertebral endplates and preventing it from moving inthe plane of the disc space. Moreover, according to the variousembodiments of implant (2), different angles can be chosen for thedevice, particularly to permit a good fixation despite possiblelordosis, kyphosis, or even scoliosis, whether it be natural,pathological, or imposed by the implant. Thus, various embodiments ofanchoring device (1) and of implant (2), by means of its radius ofcurvature and the orientation of passage (21) into which it will beinserted, can be implanted along an axis of approach substantially inthe plane of the intervertebral space, i.e., the plane in which implant(2) is implanted, which facilitates the approach of all the elements ofthe implant and the device to the intervertebral space. In oneembodiment, the arc (or arcs) described by the body of anchor (1) has(or have) dimensions and at least one radius of curvature so thatanchoring device (1) can be implanted in a vertebral endplate along anaxis of approach forming an angle comprised between 40° and 140° withthe vertical axis of the spine and, preferably, an approximately 90°angle. This angle can vary for a same anchoring device (1) depending onthe dimensions of the approaches to the vertebra and can also vary fromone anchoring device (1) to the other depending on the radius ofcurvature of device (1) used (and therefore the angle formed between itsanterior and posterior ends). Furthermore, this present application alsodescribes various embodiments of anchor (1) in which the body comprisesat least one straight (uncurved) plate (10). Note that in the case ofstraight anchors (1) (i.e., comprising at least one straight plate), theapproach axis may preferably not be substantially in the plane of thedisc space but may be oblique. This type of oblique axis is notgenerally preferred because of the encumbrance of the access tovertebrae but it is still possible to use in some circumstances. Theimplants (2) used with such straight anchors (1) preferably comprise atleast one straight passage (21), oriented toward at least one vertebra,along an oblique path (not perpendicular to the axis of the spine)between the periphery of the spine and the vertebrae. Theinstrumentation used with such implants (2) with straight passages andsuch straight anchors (1) preferably will have a contact surface withthe implant, at the anterior end, inclined with respect to itslongitudinal axis (antero-posterior according to the convention used inthe present application), so as to allow an oblique approach axisrelative to the vertebrae. The grooves (3011) in the head (30) of theguide (3) preferably will be straight, so as to guide the straightanchor (1), and arranged for bringing the anchor facing the entrance ofthe straight passage (21) in the implant. Furthermore, variousembodiments of anchor (1) may also have a body comprising at least twostraight plates (10) (or plate portions) forming an angle between eachother. These straight plates (10) (or plate portions) may for example belinked by at least one connective portion forming such angle (forexample thanks to a curvature of this connective portion). These variousembodiments may for example be used in association with implants (2)comprising a curved passage (21), for example so as to facilitate thepassage of anchor (1) and/or assure a minimum play of anchor (1) withinthe implant (2), thanks to contact of various parts or portions of theanchor (1) with various parts or portions of inner walls of the passage(21). Various embodiments of anchor (1) may also have a body comprisingat least one straight plate (10) (or plate portion) and at least onecurved plate (10) (or plate portion). These various configurations ofthe body of anchor (1) allow providing various embodiments of potentialobjects of the invention, concerning anchors comprising variousportions. These particular objects can be configured to solve theproblem(s) of facilitating the passage of anchor (1) through the implant(2) and/or to improve the stability of anchor (1) within the implant(2). In the case where such objects do not comprise rib (11), theimplants and instruments that may be associated therewith may notcomprise grooves (211, 3011). These particular objects (i.e., any ofthese embodiments comprising at least one straight and/or curved plate(or plate portion) in their body) may also comprise or not, according tovarious embodiments, any technical feature (or combination of technicalfeatures) described for any element (or combination of elements) of anyobject (or combination of objects) disclosed in this application, aslong as they are not incompatible, in particular because the structuraladaptations that may be required by such isolation or combination offeatures are directly derivable from the appreciation of the presentdisclosure.

Anchoring device (1) generally cooperates with at least one passage (21)crossing through a portion of the implant that it is intended to affix.Such a passage can be a conduit or a channel, for example, of shapes andsizes arranged for the passage of the anchoring device, particularly incross-section (for example, a substantially rectangular cross-sectionwith rounded angles). Preferably, passage (21) is straight, so as tofacilitate its machining, and its dimensions are arranged for thepassage of a curved and rigid anchoring device (1) without requiringdeformation of this device regardless of its radius of curvature. Invarious embodiments in which anchor (1) is curved, the height (of theopening) of the passage is therefore preferably slightly greater thanthe thickness of anchoring device (1), sufficiently to allow the passageof this device inside passage (21), without deformation regardless ofits curvature and its rigidity, but sufficiently small to assure a goodretention of implant (2) by anchoring device (1), without too much playof the device inside passage (21). In certain embodiments of theinvention, the width of passage (21) can be substantially equal to thewidth of device (1) so that this device has little or no lateral playonce it is inserted into passage (21). The length of anchoring device(1) may be adapted to the length of passage (21) to be crossed and thedepth to which it must penetrate in the vertebral endplates.

Rib (11) generally enhances the rigidity of anchor (1) and inhibitsdamage to the vertebrae from “cutting” in the direction of the width ofanchor (1). To inhibit this movement in the direction of the width ofthe anchor, hereinafter designated “transverse” for simplicity (it istransversal to the length of the anchor), rib (11) preferably will havea sufficient height for effective interlocking, by offering asufficiently large surface to hold the anchor transversely. Thus, rib(11) forms a sort of fin inhibiting the anchor from cutting the vertebraby transverse movements, which enhances fixation into the vertebra.Furthermore, increasing the rigidity of anchor (1) generally tends tostrengthen its fixation in the vertebrae: the plate usually will nottwist or bent, thus presenting less risk of ejection from the vertebra.Various embodiments of anchor (1) comprising at least one rib thereforeoffer a good hold in 2 planes, instead of only one in the absence ofsuch a rib (11).

In various embodiments of anchoring devices (and eventually of implantand/or instrument which may be associated therewith), the width and/orthe height of the rib (11) can vary along the longitudinal axis of body(10). Thus, for example, as some of the figures show, rib (11) starts toproject near the anterior end of the anchor and its height increasesprogressively toward the posterior end. This height of rib (11) can beconstant over a given part, for example near the posterior end, or canvary along the entire length. Moreover, in order to facilitate thepenetration of rib (11) into the bone tissue, the peak of rib (11), i.e.its upper part (the one opposite the plate), can be sharpened over atleast a part, for example near the anterior end. For example, the ribcan have chamfers on its lateral sides. In the example of FIG. 18A, theanchor (1) comprises two ribs (11) on its convex face, each ribcomprising a chamfered portion (113) and a plane portion (114). In thisexample, the chamfered portion (113) is located close to the posteriorend and the implant can thus comprise grooves which depth has a shapecomplementary to this chamfered portion (113), while portion (114) isplanar close to the anterior end. It will be understood that it ispossible to inverse this configuration, in particular for having asharpening of the chamfered portion (113) at the anterior end, so as tofacilitate the penetration into the vertebrae, or provide diverseconfigurations with several different portions. Likewise, the width ofthe rib (in the direction of the width of the plate) can also vary, forexample becoming thicker toward the posterior end, either by thissharpening of the anterior end, or by a pronounced thickening of theposterior end of the rib forming a structure for stabilizing anchor (1)in implant (2), like the ones that are described elsewhere in thisdisclosure.

Generally, as previously mentioned, anchoring device (1) is designed tobe inserted through a passage (21) crossing at least a portion ofimplant (2), in order to penetrate into at least one vertebral endplateand affix implant (2) onto this vertebral endplate by means of at leastone stop holding the implant. Longitudinal rib(s) (11) is (are)therefore designed to cooperate with at least one groove (211) createdin passage (21) of implant (2). This cooperation between rib (11),forming a sort of guiding fin, with groove (211) in passage (21), can beconfigured to strengthen the fixation of anchor (1) in implant (2),notably by reducing the transverse play of the anchor (in the directionof the plate width). Increasing the height of this rib between theanterior end and the posterior end, combined with the constancy of thisheight near the posterior end, as can be seen especially in FIGS. 6A to6G, for example, can facilitate the penetration of the rib into the boneand provide a posterior end of constant size stabilizing the anchor inthe implant by cooperation between rib (11) and groove (211). In certainother embodiments, the height of rib (11) may reach a maximum at a givendistance from the posterior end, for a given portion (111), and thendecrease in the direction of the posterior end. For example, as isparticularly visible in the embodiments shown in FIGS. 5E and 5F,portion (111) corresponds to the portion of rib (11) that remains ingroove (211) of passage (21) once the anchor is fully inserted in theimplant (once the anchor comes to be stopped on the implant to hold itagainst the vertebra). In some of these embodiments, the transitionbetween this portion (111) and the rest of the rib can be configured toform a shoulder functioning as a stop (112) on a surface (220) at theoutlet of passage (21), so as to hold the anchor in the implant byopposing the withdrawal of anchor (1). The lower but non-null height ofportion (111) allows it to inhibit transverse play of the anchor, but aportion (111) of constant height (even if less than the rest of the rib)may provide this function just as well as the one shown in FIGS. 5E and5F with a progressively-decreasing height. In these embodiments, rib(11) therefore comprises at least one notch (112) situated at a distancefrom the posterior end arranged so that notch (112) is stopped on a stopsurface (220) at the end of passage (21) of implant (2). This surface(220) may be outside the passage, but it is preferably formed by theoutlet of the passage: the junction between the inner surface of groove(211) and a surface outside the passage, such as (in the examples shown)the inner surface of the implant wall (i.e., a surface inside the cage,in the embodiments where wall (28) of the cage defines a cavity (26), asshown in the figures). It is understood that due to the presence of thisnotch (112) on rib (11), so that this rib can pass into groove (211) andclear notch (112), which comes to be stopped on surface (220) of theimplant, a slight deformation of the portion (215, FIG. 5E) of theimplant (and/or the bottom of groove (211) if the configuration of theimplant allows it) may be necessary, in particular because the anchormay not be deformable, or less deformable than the implant. This slightdeformation is often possible for intersomatic cages made of solid butrelatively deformable material, such as PEEK. It will be noted that itis also possible to have such notch (112) on the anchor somewhere elsethan on the rib. Thus, the invention foresees diverse embodiments ofanchors and implants in which the anchor comprises at least one notch(112) intended to abut a stop surface (220) of the implant, which can bewithin or at the exit of the passage (21).

In some configurations, the anterior end of anchor (1) is designed topenetrate into a vertebra adjacent to the implantation's location of theimplant (2) to be affixed. In certain embodiments of anchor (1), forexample as shown in FIG. 1, the anterior end has at least one chamfer(15) or a bevel facilitating the penetration of anchor (1) into thevertebra. In some embodiments, this anterior end can comprise a cutout(13), for example in the form of a notch as shown in FIG. 1,facilitating the penetration of the anterior end into the vertebralendplates. Also note that the inner edges of the notch may or may not besharpened. Generally, since the anterior end is the one designed topenetrate into the vertebral endplate and may guide the rest of anchor(1), it is preferred that it be made so as to facilitate penetrationinto the bone tissue. Thus, the figures of the present application showan anterior end configured substantially into the shape of a point (asfurther explained elsewhere in this disclosure). It is understood thatthis end can be sharpened (or ground), but that since bone tissue can berelatively resistant, it is preferable to preserve the integrity of thisanterior end. Thus, as can be particularly seen in FIG. 1, for example,the anterior end preferably has a chamfer on each of the faces of plate(10) and the lateral sides of the plate are beveled so as to reduce thewidth of the anterior end. Preferably, these bevels terminate at adistance from one another and the anterior end is therefore terminatedby a sharp edge (the one where notch (13) is made in FIG. 1, forexample). On the other hand, as previously mentioned, it is preferablefor anchor (1) to penetrate easily into the vertebrae without riskingsplitting them beyond the dimensions of anchor (1). Thus the lateralsides (or edges) of plate (10) (of the body in general) will preferablybe flat, as shown in most of the figures. Hence, in general, the lateralsides of the plate (10) of the anchor (1) preferably are flat (as forexample on FIGS. 2G, 2H and the majority of figures showing the anchor),so as to avoid splitting the vertebrae. These sides (or edges) areparticularly (but not only) adapted to the embodiments in which theanchor doesn't comprise any rib. In other embodiments, the sides may beless flat, for example rounded or chamfered, as visible on the examplesof FIGS. 6D, 8F, 18A, 18B, or even sharpened so as to easily penetrateinto vertebrae, but in this latter case, the anchor will preferablycomprise a rib. Indeed, since the presence of a rib (11) reduces therisks of transverse movement of the anchor, it will also reduce therisks linked to the sharpening of the lateral edges of plate (10).

To enhance an anchor's ability to hold an implant (2) against avertebra, various embodiments provide for it to be stopped against atleast one surface of the implant that it is intended to affix, so as tohold the implant against the vertebral endplate, preferably firmlypressed against it. In various embodiment of anchoring device (1), thebody accordingly comprises at least one retaining stop (14). Retainingstop (14) preferably has at least one stop surface oriented facing theanterior end. Preferably, this surface is oriented approximatelyperpendicular to the longitudinal axis and is facing the anterior end,whether it is positioned at the posterior end or further towards thefront. This retaining stop (14) is designed to cooperate with at leastone stop surface of a complementary stop (214) provided on implant (2)that device (1) is designed to affix, in order to hold implant (2)against the vertebra in which anchoring device (1) is designed to beanchored. In various embodiments, stop (214) preferably comprises atleast one stop surface oriented facing the posterior end (i.e., towardthe periphery of the implant), in order to cooperate optimally withretaining stop (14). These cooperating stop surfaces can have variousconfigurations, for example, flat, curved, prismatic, and so on. Notethat retaining stop (14) is preferably at the posterior end, as most ofthe figures of the present application show. In many configurations,retaining stop (14) is positioned at the level of (i.e., at or in thevicinity of) the posterior end so that it is located at, or near to, theentrance to passage (21) in the implant, abutting the complementarysurface of stop (214) of the implant. This surface of the complementarystop (214) may, for example, be a surface of the peripheral wall of theimplant, but it may preferably be formed by a recess, so that stop (14)doesn't protrude from (or extend beyond) the implant when anchor (1) isfully inserted therein. Furthermore, it is understood that stop (14) canbe further toward the front of the anchor, so that it can be foundinside passage (21), for example, as long as a complementary stopsurface (214) of the implant is suitably positioned. The position ofretaining stop (14) at the level of the posterior end, however, in manyembodiments has the advantage of offering a good hold of the implant,particularly when the anchor is configured to contact the implant fromthe entrance of the passage up to the outlet. In addition, thisposterior position may be preferred when configuring the implant (2) andthe anchor (1) to facilitate an intentional withdrawal of the anchor, asdiscussed for various configurations elsewhere in this disclosure.

In certain embodiments of anchor (1), retaining stop (14) comprises atleast one part protruding from at least one of the faces and/or sides(or edges) of the anchor (1). For example, the retaining stop (14) maycomprise at least one projecting lug. For example, as is particularlyvisible in FIGS. 2G, 2H, 6D, 8D, 8E, 8F, 9A-C, 10A-C, retaining stop(14) comprises two projecting lugs on a same face of anchoring device(1), in particular the convex face in these embodiments where the anchorcurvature is oriented in the direction of the depth of plate (10). Inother configurations, at least one projecting lug can be provided on anyface and/or sides (or edges), or at least one lug can be provided oneach face and/or sides (or edges), or there can be any other variant inthe same spirit. In the example of FIG. 13G where the anchor has acurvature oriented in the direction of the width of plate (10), it isalso possible to provide at least one retaining stop (14) on at leastone of the faces of the plate and the example of FIG. 13G is not at alllimiting. In certain embodiments of anchor (1), retaining stop (14)comprises at least one projecting lug on at least one lateral side oredge of the body of anchoring device (1). Preferably, at least one lugwill be positioned on each of the 2 lateral sides, so as to improve thehold, as shown, for example, in FIGS. 5F, 6E, 6F, and 6G. In certainembodiments of anchor (1), retaining stop (14) comprises at least oneprojecting lug on at least one lateral face of rib (11), preferably nearthe posterior end of the anchor, so as to avoid creating an excessivelylarge or deep recess around groove (211) for the complementary stopsurface (214). Preferably, at least one lug will be positioned on eachof the lateral faces of rib (11) at the posterior end, as shown in FIGS.7B and 7E. As these example configurations of retaining stop (14) show,the term “projecting lug” used here should not be interpreted in alimiting manner, and the precise form of the lug can vary, for examplebetween a small plate offering planar stop surfaces and a small studoffering curved stop surfaces, or any other variant, although someparticular shapes may have various advantages, for example in terms ofan efficient hold or of a voluntary withdrawal of the anchor. Inaddition, retaining stop (14) can have various orientations, so as tohold anchor (1) in the implant and hold the implant tight against thevertebra in an optimal manner. Several different retaining stops (14)can also be provided, positioned at different places on anchor (1). Insome embodiments of anchor (1) and implant (2), the shapes of retainingstop (14) and complementary stop (214) can be arranged so that stop (14)of the anchor is mated with or locked to stop (214) of the implant, forexample by locking lugs engaging a recess. In the case of anchors (1)with two curved plates connected by an uncurved portion or in the caseof a single plate with a curved portion (hook-shaped, such as inpublications FR 2,879,436, WO 2006/120505 and US 2006/0136063, each ofwhich is incorporated herein by reference, particularly in the case offixation of prostheses), this portion can serve as a retaining stop,cooperating with a shaft or at least one surface situated at theentrance of passage (21), for example. Anchoring device (1) is removablein numerous embodiments and can be implanted in the vertebrae and matedwith the implant after it is installed between the vertebrae, whichallows possible adjustment of the position of the implant between thevertebrae before definitive fixation by anchor (1). In some embodiments,the retaining stop can be used to pull the anchor (1) to remove it fromthe vertebrae, and the implant if necessary (e.g., in the case of acurved hook or a stop (214) providing a way to pull on a least a part ofretaining stop (14)). Note that the example in FIG. 7E, and similarconfigurations, can be disposed somewhere else than on the rib (becausethe anchor doesn't comprise any rib or when the rib stops before rearend), and configured on a leg (or lug) projecting from plate (10). Astop formed away from the plate (through the rib or a protruding leg)can also be used to pull the anchor for withdrawal, especially if theentrance passage has a recess for access by an extraction tool.

In some embodiments, the body of anchor (1) comprises at least onewithdrawal stop or fastener opposing the withdrawal of anchoring device(1) from implant (2), for example by cooperating with at least onecomplementary withdrawal stop (212) on the implant (2). The withdrawalstop can, for example, take the form of a latch comprising at least oneflexible lug (12) (or tab), for example oriented substantially towardthe posterior end of the anchor or of other structures to fasten anchor(1) with implant (2). As illustrated in FIGS. 14A and 14B, in variousconfigurations these lugs are designed to retract (into the width of theplate in this example, or into the depth of the plate in other examplesdescribed herein, or even into the width or into the depth of the rib inother examples herein), in order to allow the anchor to pass intopassage (21) of implants (2). The orientation of the lug may varydepending on various embodiments, particularly according to the desiredspacing of the leg (12) compared to the rest of the body of the anchor(1). In some preferred configurations, the lug is flexible. It will benoted that this flexibility of the lug can be obtained by the fact thatthe lug is thin even though its material is substantially rigid, and/orby a substantially flexible material and/or by the shape of the lug. Forexample, the lug may preferably have a substantially curved shape, toenhance flexibility for it to engage at least one surface or otherretaining structure of the implant. The withdrawal stop need not beoriented just toward the posterior end, but in configurations where alug engages a surface or other structure of an implant (even if notaligned with the longitudinal axis) its direction is designated here assubstantially or approximately to the posterior end because preventingwithdrawal usually will be facilitated by such an orientation. Once theanchor is advanced into implant so that contact with the inner wall(210) of passage (21) is clear, flexible lug (12) is made to unfold,from which position it can abut a complementary withdrawal stop (212) ofthe implant, comprising at least one stop surface arranged to receivethe free end (122, FIG. 14A) of flexible lug (12) and thus prevent thewithdrawal of anchor (1) or at least prevent anchor (1) from coming outof implant (2) due to the effect of the forces exerted on the anchorand/or the implant. Note that in the majority of the figures showingflexible lugs on the lateral sides of plate (10) and as is particularlyvisible in FIGS. 14A and 14B, a portion of the free end (122, FIG. 14A)of flexible lug (12) extends beyond the periphery (for example thelateral sides) of plate (10) so as to form the stop (when the lug isunfolded), while the attachment end (121, FIG. 14A) of flexible lug(12), generally solid with the plate, is preferably formed within theperiphery (for example lateral sides) of plate (10) so as not to opposethe insertion of the device into passage (21). It is noted that“flexible lug” is used here in a non-limitative manner and may refer toa flexible portion formed of one piece with the rest of the anchor, orto a separate flexible piece attached to the body (10) of the anchor, oreven to an piece (either flexible or inflexible) attached to the body(10) of the anchor that flexes at an articulation area. In theseconfigurations, flexible lugs (12) fold easily without hindering theinsertion of the anchor into the implant and easily unfold to engage andabut at least one surface of withdrawal stop (212). Generally, it ispreferable that flexible lugs (12) be positioned on the anchor on aportion that will not be in contact with the bone tissue when the anchorhas been inserted into the vertebra, so as not to impede the unfoldingof these flexible lugs. In other configurations, however, (for example,those shown in FIGS. 5D, 7B, 8G) the flexible lugs can be positioned onthe anchor so that they unfold inside the passage, to be stopped onwithdrawal stop (212) formed by an upper or lower surface of implant(2). In these examples, the unfolding of the lugs at the outlet ofpassage (21) may be impeded by the bone tissue, which may be offset byother advantages such configurations provide, such as simplerconstruction and potentially greater structural integrity of theimplant. In other embodiments, examples of which are shown in FIGS. 2C,2E, the flexible lugs are positioned on the anchor so as not to extendbeyond passage (21) in the implant once anchor (1) is inserted withinand passage (21) then comprises at least one structure (for example, arecess surface) forming withdrawal stop (212), as is particularlyvisible in FIGS. 15B, 15C, 15D, and especially 15F. It is understoodthat walls (210) of the passage will then be widened over a givenportion to form withdrawal stop (212) where these lugs (12) are locatedwhen the anchor is fully inserted in the implant. Thus, in this example,the dimensions of the outlet of passage (21) are greater, at least alongone axis, than those of its entrance, at least along a direction or anaxis not parallel to the axis of the passage. Withdrawal stop (212) canbe made by machining from the passage outlet, along an axis orientedparallel to the longitudinal axis of the passage. However, in certainvariants, withdrawal stop (212) can be made along an oblique axis, sothat the recesses are formed inside the passage without widening theoutlet. In the case of a widened passage outlet, the play of anchor (1)in passage (21) will remain limited by the passage entrance and/or bythe cooperation between rib (11) and groove (211). Preferably, theselugs will not be disposed so close to the posterior end as to require adeep recess realized from the outlet of passage (21) to form withdrawalstop surfaces (212).

FIGS. 13D, 13F and 13G show one example of embodiment similar to theones described above comprising lugs on the sides of the plate, but onanchors curved in the direction of the plate width. The flexible lugs inthese examples are disposed on the sides (concave and convex) of theplate. However, in the embodiments with the anchor curved in thedirection of the plate width (anchor with vertical orientation),flexible lugs (12), for example, can be provided on the lateral faces ofthe plate (for example, on the same side of rib (11) or the oppositeside), or on rib (11), in each case in accordance with the discussionelsewhere in this disclosure.

In certain embodiments of anchor (1) and implant (2), flexible lug(s)(12), instead of (or in addition to) being positioned on at least oneside of the plate, can be positioned on at least one of the surfaces ofthe plate. FIGS. 9A, 9B, and 9C show illustrative examples of theseembodiments, with flexible lugs (12) situated on the convex face ofanchor (1), on either side of groove (11). Of course, these lugs can beprovided on the concave surface, on both surfaces, or a single lug canbe provided on one or both faces. In some configurations, especially ifthe size of portion 215 (e.g., FIG. 5E) of implant (2) allows it, aflexible lug (12) can be provided on the concave face, cooperating witha withdrawal stop (212) inside or on the upper surface of portion (215).In this case, a recess (240, FIGS. 15F, 18D, 18F) can also be providedon this side of the passage, to allow the flexible lug to be disengaged,as explained elsewhere in this disclosure.

In these examples, note that the position of the lugs, on the one hand,between the anterior and posterior ends, and, on the other hand,laterally on the face, can vary. Preferably, these lugs will not bedisposed so close to the posterior end that a deep recess realized(spared) from the outlet of passage (21) to form withdrawal stopsurfaces (212) is required, as previously discussed. Depending on theposition of flexible lugs (12), withdrawal stop (212) may be formed invarious places on the implant. For example, in the case of lugs close tothe posterior end like in FIGS. 9A and 9B, withdrawal stop (212) may beformed by recesses, for example as shown in FIG. 9F, created in a wall(210) of passage (21): either recesses near the lateral sides of thepassage in the case of FIG. 9A, or recesses adjacent to the groove inthe case of FIG. 9B. Lugs disposed further from the posterior end, likein the example of FIG. 9C, can engage a surface outside the passage, asshown in FIG. 9G.

In certain embodiments, lug(s) (12), instead of (or in addition to)being positioned on at least one side or at least one face of the plate,can be positioned on the peak or on at least one side of rib (11). FIGS.10A, 10B, and 10C show illustrative examples of these embodiments. InFIG. 10A, the rib (11) comprises two flexible lugs (12) extending beyondthe sides of the rib. These two lugs preferably will be sized to bewithin or to approximate the width of the rib when folded. In FIG. 10B,the rib comprises a lug on each side, in this configuration offset fromone another in the longitudinal axis. These lugs may also havedimensions that approximate or do not exceed the width of the rib oncefolded. In the example of FIG. 10B, these lugs are not as tall as rib(11) but they may be made as tall or taller. In the 2 examples of FIG.10C, the lugs are created at the peak of the rib, at variable positions:the lug of the top anchor is situated further from the posterior endthan the lug of the bottom anchor. In these examples, the lugs arepreferably sized not to extend beyond the height of the rib, but theycan have various dimensions or configurations.

In most of these configurations, a withdrawal stop (212) is disposed inthe implant and arranged to cooperate with the flexible lugs, dependingon their position on the anchor and their orientation. For example, inFIG. 10G, the anchors of FIG. 10A abut at the outside of passage (21)and withdrawal stop (212) is, in this example of an intersomatic cagehaving an inner cavity (26) formed by the surfaces on either side of theoutlet of groove (211), inside the cavity in the cage. In FIG. 10H, thetwo offset lugs of anchor (1) of FIG. 10B come to be stopped in a recessalong groove (211) for the one closest to the posterior end (the top onein FIG. 10H) and, for the one further from the posterior end, on asurface at the outlet of groove (211), inside the cavity in the cage.Similarly, depending on the position of the lugs along the longitudinalaxis, in the example of FIG. 10I, a recess will be provided along groove(211) to form withdrawal stop (212) (see the bottom anchor in FIG. 10I),but for a lug further from the posterior end, like the top one in FIG.10I, withdrawal stop (212) will be formed by a surface at the outlet ofgroove (211), inside the cavity in the cage.

Note that in these various embodiments where the flexible lugs arepositioned at a distance from the posterior end so that a recess must bemade for unfolding the lugs, withdrawal stop (212) thus created can bearranged to have 2 stop surfaces, together forming an angle (preferablyclose to 90°), so that the free end of flexible lug (12) comes to reston one of them and opposes withdrawal of the anchor and that the othersurface inhibits deformation of the lug when anchor (1) is subject toforces tending to cause its withdrawal from the implant, as can beparticularly seen in the examples of the bottom anchor of FIG. 10I or,in a less confined manner (i.e., with a larger recess), on both anchorsof FIG. 9F. Note that in those embodiments where the lugs (12) areflexible on the convex or concave sides of the anchor (1) and cooperatewith a recess in the implant, lugs (12) can be made flexible to be apartfrom the body of the anchor a distance greater than the depth of theirstops in the implant, so they exert force on the implant and helpstabilize the anchor (1) and limit its play in the implant (2), whichcan be particularly advantageous when the passage (21) has a heighthigher than the anchor, in particular when the passage is straight.

In certain embodiments, the free end of the lug can be beveled, as canbe particularly seen in FIGS. 10G, 13F, preferably with an anglearranged as a function of the orientation of withdrawal stop surface(212) to hold the anchor in an advantageous manner. The free end alsomay be beveled to facilitate unfolding lug (12) despite tight adjustment(or alignment) of lug (12) and withdrawal stop (212), such as, forexample, in the case of FIG. 9F, where it appears, for purposes ofillustration, that the unfolding of lug (12) risks being impeded by thestraight shape of the free end. Generally, for particularly advantageousconfigurations, the position of withdrawal stop (212), and theorientation of its stop surface(s) receiving the free end of theflexible lug, are dependent, and vice versa, on the position of flexiblelug (12) on anchor (1) and the shape of the free end of flexible lug(12).

As mentioned in this disclosure, various configurations of anchor (1)may comprise a recess allowing flexible lugs to be fully folded so theydo not project beyond the body of the anchor and impede the insertion ofthe anchor in passage (21). In the embodiments with flexible lugs (12)positioned on the lateral sides of the anchor, as shown, for example, inFIGS. 14A and 14B, this recess may be formed by a thinner width of plate(10) at lugs (12) than along the rest of the body of anchor (1). In theembodiments with flexible lugs (12) positioned on at least one of thefaces (concave or convex) of curved plate (10) of the anchor, as shown,for example, in FIGS. 9A, 9B and 9C, this recess may be formed by athinner part of plate (10) at lugs (12) than along the rest of the bodyof anchor (1). In the embodiment where the flexible lug is positioned onrib (11), the size (height or width) of folded flexible lug (12) will beless than the height or width, respectively, of rib (11), so as not toimpede the insertion of anchor (1) into passage (21).

It is understood from the examples of flexible lugs (12) discussedherein that numerous variants are possible and that the illustrative andnon-limiting examples described here in reference to the figures serveto illustrate the diversity of these possibilities. Although certainconfigurations may be more advantageous than others, any extreme orintermediate configuration, including those among or between thosedescribed herein, are within the scope of the invention.

In certain embodiments of anchor (1), the body may be configured withnotches (16) oriented to oppose the withdrawal of device (1) once it isimplanted in a vertebra. Preferably, these notches will be present onlyalong the portion of the body of anchor (1) that is designed to emergefrom the passage when the anchor is fully inserted in the implant. Ascan be particularly seen from the nonlimiting examples shown in FIGS.2H, 6D, and 8F, these notches (16) can vary in number, size and shape.

In certain embodiments of anchoring device (1), at least one opening(17) through plate (10) allows bone to grow through the opening oncedevice (1) is implanted, as can be particularly seen in the nonlimitingexamples shown in FIGS. 2H and 6D. Such openings (17), by permittingbone tissue to grow through plate (10), inhibits anchor (1) from comingout of the vertebra once the osteosynthesis is completed. In someembodiments, a rib (11) may be used advantageously to mitigate anystructural weakness of plate (10) that may be caused by opening (17).

In certain embodiments, the ability to readily withdraw the anchor ispreferred, and in those embodiments openings (17) and/or notches (16)would be generally undesirable. Certain embodiments described hereincomprise at least one mechanism allowing removal of anchor (1), and inthose embodiments the size of these openings (17) may be limited so thatthey can play their role of holding anchor (1) without impedingwithdrawal of anchor (1) by means described herein. Likewise, the shapesand sizes of notches (16) can also be adapted so as to opposespontaneous withdrawal of anchor (1) while permitting intentionalwithdrawal by means of the mechanisms described herein. Theseembodiments are thus not necessarily exclusive, and depend on the sizesof openings (17) and/or the shapes and sizes of notches (16).

In certain embodiments, anchor (1) (and/or implant) comprise(s) awithdrawal mechanism facilitating the intentional withdrawal of theanchor from the implant and the vertebra using an anchor extractiontool, if necessary. The tool for extracting anchoring device (1) canhave various forms, such as, for example, a shaft curved at its end(like a hook) so as to penetrate into a recess and allow the withdrawalof the anchor by pulling on a shaft. For example, in certainembodiments, retaining stop (14) may be configured with a catch tofacilitate withdrawal of anchor (1). In some of these embodiments, sucha catch can be obtained by making retaining stop (14) wider thancomplementary stop (214) of implant (2) on which it comes into contact.Complementary stop (214) or a nearby area of implant (2) may beconfigured with a space or gap that allows inserting an anchorextraction tool to pull on retaining stop (14). When anchor (1)comprises at least one withdrawal stop or latch opposing the withdrawalof anchor (1), this stop or latch can be configured to be released andallow withdrawal of the anchor (1). For example, the free end of theflexible lug (12) may be configured so that it can be disengaged fromwithdrawal stop (212) of implant (2), through a channel emerging at theend of implant (2). For configurations with a flexible lug (12) disposednear the posterior end, a channel may be provided, for example, througha portion of the implant from the posterior wall to withdrawal stop(212), for example beside groove (211) or beside passage (21) in ageneral way, depending on the position of flexible lug (12). Forexample, FIGS. 15F, 18D and 18F shows examples of a recess (240)emerging at the entrance of the passage (21), into which an anchorextraction tool may be inserted, for example to disengage the flexiblelug (12) of an anchor like the one shown in FIGS. 11B and respectively18A (and 18B) and/or to pull on a retaining stop (14) like the one shownin FIG. 8E and/or another mechanism as explained elsewhere herein. Otherembodiments described elsewhere herein allow disengagement or unlatchingof flexible lug (12) with a mechanism that does not require such arecess (240) or channel in implant (2). In certain embodiments, the bodyof anchor (1) comprises, near the posterior end, at least one recess(40) arranged to receive a tool for extracting anchor (1) and allowingwithdrawing the anchor by pulling up. FIGS. 6D, 6E, 6F, and 6G showexamples of such a recess (40), created through plate (10), near theposterior end. In certain embodiments (not shown), recess (40) can becreated in the rib, for example near the posterior end. Such a recess(40) in plate (10) or rib (11) of anchor (1) can, according to theconfiguration of the implant at the entrance of passage (21), be madeaccessible by means of a recess (240) such as the one shown in FIG. 15F.In FIGS. 6D, 6F, and 6G, rib (11) does not extend up to the posteriorend of the anchor, so as to leave sufficient space for providing suchrecess (40) in the anchor (1). In the example of FIG. 6E, the ribextends to the posterior end, but a recess (40) will be created at leaston one side of the rib (both sides in the example shown). In the exampleof FIG. 6G, recess (40) of the anchor is open on the posterior end, sothat the tool can directly access this recess (40) for withdrawal of theanchor, without relying on a recess (240) in implant (2) forintroduction of an extraction tool, as typically would be used for theexamples of FIGS. 6D, 6E, and 6F. Although open, this recess (40) stilloffers a catch surface backing the posterior end for pulling on theanchor toward the posterior end to withdraw it from the vertebra. Notethat in FIG. 15F, an implant (2) is shown configured to receive anchorsof the types of FIG. 11B, and also some configurations of the devicesshown in FIGS. 11F, 10C, and 12, since it comprises a recess (240) forinsertion of the tool for unlatching flexible lug (12).

In certain embodiments, anchoring device (1) comprises a mechanism thatwill assist stabilizing it in passage (21) in the implant. In certainembodiments, for example, a curved anchor is provided to pass through astraight passage of the implant, without deformation of the anchor (1)in spite of its curvature. These embodiments of implants (2) withstraight passage (21) are easier and less expensive to make than theembodiments of implant (2) with curved passage (21). However, for acurved anchor to pass through the straight passage, the height ofpassage (21) must be at least slightly greater than the thickness ofplate (10) in the embodiments of anchors with horizontal orientation(curved in the direction of the plate depth), or greater than the widthof plate (10) in the embodiments of anchors with vertical orientation(curved in the direction of the plate width). It is preferable, though,that the anchor has little or no play in passage (21) of implant (2), atleast to prevent movements of the anchor (and/or the implant) that willtend to make the anchor come out of the vertebrae. As noted elsewhere inthis disclosure, the body of the anchor in some configurations can havevarious radii of curvature between the two ends (anterior andposterior). In certain embodiments, the curvature of anchoring device(1) at the posterior end can be configured to engage wall (210) ofpassage (21) sufficiently to improve the hold of anchoring device (1) onimplant (2). In certain embodiments, rib (11) may comprise on its peak(i.e., on its upper surface, the face opposite the plate) and at aportion (111) near the posterior end, a planar surface (111 a, FIGS. 6B,6C) limiting the play of device (1) in implant (2) with an interferencefit with a planar surface of the bottom of groove (211) of passage (21)of implant (2). In certain variants of these embodiments, the body has,at a portion (110) close to the posterior end and on its face oppositethe one with rib (11), a planar surface (110 b) limiting the play of thedevice in passage (21) of implant (2) with an interference fit withplanar surface (111 a) of the rib, as shown in FIG. 6B. In otherembodiments, curved plate (10) of the body is extended at a portion(110) near the posterior end by a straight plate whose planar surfaces(110 a, 110 b, FIGS. 6A, 6C) limit the play of the device in passage(21) of implant (2) by being slightly thicker than the rest of plate(10). FIG. 6C shows a combination of these planar surfaces (110 a, 110b) of plate (10) with a planar surface (111 a) of rib (11). It isunderstood that portions (111 and 110) close to the posterior endgenerally correspond at most to the entire length of passage (21), butthey are preferably shorter, since the insertion of the anchor throughpassage (21) could be inhibited if they were too long. An instrument(e.g., 3, 4) (described elsewhere in the disclosure) for insertinganchors (1) into the vertebrae through an implant is a potential objectof the invention, and therefore it is preferable for anchors (1) to beconfigured to pass through this instrument (3, 4). Thus, preferably athickened portion, possibly planar, on a part of the length of theanchor, will not impede guidance of the anchor into and through theinstrument. Thus, in various embodiments, the anchor may be stabilizedin the passage by means of at least one thickened stabilization portion(20), typically having a width less than the width of plate (10) but athickness greater than that of the rest of plate (10), such as, forexample, as shown in FIGS. 6D, 6E, 6F, 6G, 14C, and 14E. Stabilizationportion (20) should not prevent retaining stops (14) from being stoppedon their complementary stop (214) in the implant, so when theseretaining stops are created on one of the faces of the plate, thestabilization portion (20) preferably will thus be positioned on theface opposite the one comprising retaining stops (14), which willimprove their function of stop. Also, in some embodiments depending onthe configurations of various elements it is preferable forstabilization portion (20) to be on the face opposite the one comprisingthe rib to provide better engagement of the rib in its groove, inparticular when it will be preferred to use this stabilization portionin combination with a planar surface (111 a) of rib (11). Note that incases where the anchor (1) combines the stabilization portion (20) andrecess (40) for withdrawal, the portion (20) preferably does not extendto the posterior end of the anchor, as particularly visible in FIGS. 6D,6E, 6F and 6G, to facilitate access to recess (40) for the withdrawal ofthe anchor (1). During insertion of various configurations of anchor(1), the stabilization portion may impede passage of the anchor if theincrease in thickness is too abrupt. Thus, stabilization portion (20)may comprise at least one chamfer, for example where it meets the plate,substantially toward the anterior end, for example as visible in FIGS.6D, 6E, 6F, 6G, 14C, and 14E, so as to provide a progressive increase inthickness up to the optimal thickness that presses anchor (1) in passage(21) and thus limits its play. Similarly, planar surfaces (110 a, 110 b,111 a) mentioned above can be integrated progressively. In someconfigurations, the height of the rib, in particular in the case of aplanar surface (111 a), whether alone or in combination with otherplanar surfaces or the stabilization portion, can be greater at portion(111) near the posterior end than on the rest of the rib, so that thisportion (111) of rib (11) serves to stabilize the anchor (1) in implant(2). Note also that the thickness of thickened portions (20 or 110)preferably will still be slightly less than the height of passage (21),so as to limit play without completely eliminating it (and/or the heightof the rib on portion (111) will be slightly less than the depth ofcomplementary groove (211)). Nevertheless, in certain variants, thisthickness (and/or height) will be equal to or even somewhat greater thanthe height of passage (21) (and/or depth of the groove, respectively),notably in the case of intersomatic cages whose material (such as PEEK,for example) allows a slight deformation (for example a deformation ofportion (215) of the cage shown in FIG. 5E).

The present application foresees various embodiments of objects such asanchors (1) comprising no rib (11), in which anchor (1) is curved butthe passage (21) is straight (and higher than the height of anchor) andin which the plate (10) comprises the stabilizing portion (20) and/or atleast one of the portions having a plane surface (110 a, 110 b)described in the present disclosure. The implants and instruments thatmay be associated with such anchors then need not comprise grooves (211,3011). These objects allow limiting the play of the curved anchor (1)within the straight passage of implant (2). These particular objects mayalso comprise or not, according to various embodiments, any technicalfeature (or combination of technical features) described for any element(or combination of elements) of any object (or combination of objects)disclosed in this application, as long as they are not incompatible, inparticular because the structural adaptations that may be required bysuch isolation or combination of features are directly derivable fromthe appreciation of the present disclosure.

A single anchoring device (1) may be used to anchor an implant (2) in avertebra, but in most applications at least two devices preferably willbe used to affix an implant (2) in the 2 adjacent vertebrae betweenwhich it is implanted (at least one anchor for each vertebra). Aspreviously mentioned, another potential object of the invention is ananchoring system for the implant comprising two anchoring devices (1),either identical to each other, or different, or complementary to eachother. Thus, the combinations of any of the embodiments of anchorsdescribed herein whatsoever are within the scope of the invention.

In certain of the embodiments with complementary anchors, a firstanchoring device (1) comprises a first cooperation stop (18) comprisingat least one stop surface oriented substantially facing the anteriorend, and a second anchoring device (1) comprises a second cooperationstop (19) comprising at least one stop surface oriented substantiallyfacing the posterior end. These first and second cooperation stops (18,19) are configured to cooperate with each other, so that the firstdevice (1) holds the second device (1) once they are in place in implant(2), and/or vice versa. For example, as shown in the illustrative andnon-limiting examples of FIGS. 8D, 8E, 8F, and as particularly visiblein FIG. 8H, first anchor (1) can have a first stop (18) such as a lug, ashoulder, or a tab projecting in the direction of second anchor (1)which can have a second stop (19), such as a lug, a shoulder, or a tab,arranged so that the first stop (18) and the second stop (19) abut eachother in a complementary manner. Note that in the examples of FIGS. 8D,8E, and 8F, the first anchor (the bottom one comprising cooperation stop(18)) does not need retaining stop (14) since it rests on cooperationstop (19) of the second anchor (the top one) which has retaining stops(14). However, first cooperation stop (18) of the first anchor also mayform a retaining stop (14), or vice versa. In the examples shown, theadvance of anchors (1) in the passage is blocked by retaining stops (14)of the second anchor and by cooperation stop (18) of the first anchor.In these configurations, the second anchor retains the first bypreventing it from entering too far into the passage. In return,cooperation stop (18) of the first anchor retains the second anchor andprevents it from coming out of the implant. In certain embodiments,cooperation stop (19) can be formed at least by a surface situated onthe posterior face of retaining stop (14) of the second anchor. Incertain embodiments, only first anchoring device (1) having cooperationstop (18) will have a withdrawal stop (12), such as a flexible lug (12)for example, configured to cooperate with a withdrawal stop (212) of theimplant, as shown in FIG. 11A, and in these configurations, cooperationstop (18) of first device (1) may serve as a withdrawal stop for seconddevice (1) by abutting the second stop (19). In these configurations,the second device (1) is retained on first device (1) by cooperationstops (18 and 19), and flexible lug (12) retains first device (1) onwithdrawal stop (212) of implant (2), for example as particularlyvisible in FIG. 11E. As noted, in certain embodiments only the seconddevice (1) comprising stop (19) may be configured with a retaining stop(14), since cooperation stop (18) of the first device (1) can play therole of retaining stop for the first device (1), by abutting against thestop (19) of the second device (1), which is held in this direction by aretaining stop (14).

In certain embodiments of anchoring systems with complementary anchors,cooperation stops (18, 19) may further interlock to inhibit movement ofboth the first and the second anchoring devices (1) in both the anteriorand posterior directions. An illustrative and non limitative example ofone of these embodiments is shown in FIGS. 11B and 11F. For theillustrated configuration, cooperation stop (19) of the second anchoringdevice (1) comprises a second cooperation stop surface (190), orientedsubstantially facing the anterior end, and the first device (1)comprises a withdrawal stop (here in the form of flexible lug (12))positioned so that the free end of the lug (12) (its posterior end)comes into contact with and is retained by the second surface (190) ofstop (19), thus preventing withdrawal of the first device which retainsthe second device (1) once it is in place in implant (2). Note that inthese embodiments, as mentioned elsewhere in this disclosure, a channelor recess (240) such as the one shown in FIG. 15F for example, willallow inserting an extraction tool for disengaging flexible lug (12)from second stop surface (190). In some other embodiments that do notrequire a recess or channel in the implant, as particularly seen inFIGS. 12(A-E), cooperation stop (19) of the second device comprises arecess (40) (or conduit or channel). As can be particularly seen inFIGS. 12B and 12E, this recess emerges near second stop surface (190),which allows disengaging flexible lug (12) with a tool. Note that thisrecess (40) also can be used to withdraw the anchor, as describedelsewhere herein. In various configurations, therefore, the end offlexible lug (12) (i.e., the free end of the lug) of the first device(1) can be disengaged from second stop surface (190) of stop (19) of thesecond device (1) through a recess or channel accessible from outsidethe implant and that this channel can be created either in the implantor in one of the anchors, and that a recess or channel in the anchor cancorrespond to (or also form a) recess (40) facilitating intentionalwithdrawal of the anchor.

Cooperation stops (18, 19) are shown in FIGS. 11 (A through F) and 12 (Ato E) located at the rib, but they could be disposed elsewhere on thebody of the anchor (1). By providing an interlock, an anchor retains theother (and vice versa in some configurations), helping to reduce thefootprint of the implant (and therefore its machining, which may avoidreducing its strength).

These various configurations of cooperation stops (18, 19) allowproviding various embodiments of potential objects of the inventionconcerning anchoring system with anchors comprising cooperation stops(18, 19) with or without the second cooperation stop surface (190)opposing the withdrawal, and may but need not comprise rib (11). Theseparticular objects may be configured to solve the problem of minimizingthe stop structures of the anchor thanks to the technical featuresenabling a reciprocal engagement. These diverse objects may also concernanchors having a straight body instead of a curved body. Forconfigurations without rib (11), the implants and instruments that maybe associated with such anchors may then not comprise grooves (211,3011). As noted elsewhere, in configurations comprising second surface(190), each anchor blocks the withdrawal of another. These particularobjects (i.e., any of these embodiments with the cooperation stops (18,19)) may or may not also comprise any technical feature (or combinationof technical features) described for any element (or combination ofelements) of any object (or combination of objects) disclosed in thisapplication, as long as they are not incompatible, in particular becausethe structural adaptations that may be required by such isolation orcombination of features are directly derivable from the appreciation ofthe present disclosure.

In some embodiments, as particularly visible in FIGS. 18A and 18B, theanchor has a step (123) (such as a shoulder or a notch) between the freeend (122) and attachment end (121) of the lug (12). In theseembodiments, this step (123) is intended to abut the withdrawal stop(212) of the implant when the anchor is seated, for example as seen inFIG. 18D. In some of these embodiments, the free end (122) does notengage a withdrawal stop of the implant, but instead extends to near theposterior end of the anchor, so as to be accessible for disengagement ofstep (123) by pressing the free end (122) in the direction away fromstop (212). In the example shown in these figures, the free end (122)extends to nearly the posterior end of the anchor, but is still behind arod (for example, between retaining stops 14) that may be used to pullon the anchor to withdraw it from the vertebra and implant, if desired.In this example, recess (240) in the implant provides access to the freeend (122), as particularly visible in FIGS. 18D and 18F. In someconfigurations, however, for example where the anchor is configured witha stop (14) or recess (40) or other structure that can be used to pullon the anchor (for example, a curved or hook-shaped stop or a stop withan opening), the lug may extend to the posterior end of the anchor, soit is accessible without the need for a recess (240) in the implant orby way of a less sizeable recess. In some embodiments, the attachmentend (121) of lug 12 is secured to the body in the thickness of the plate(10), which in this non-limiting example is hollowed out to accommodatethe flexible lug (12), as shown in FIG. 18B. In this example, only onelug (12) provided with the step (123) is located substantially at themiddle of the anchor (between its lateral edges) but various otherembodiments foresee at least one lug (12) provided with step (123)located elsewhere on the anchor, such as for example close to a lateraledge of the plate, and engaging a complementary withdrawal stop (212)located on an edge of the passage (21) in the implant (with somevariants comprising for example such a stop mechanism on each on thelateral edges of the anchor).

Various embodiments of the anchor (1) (and/or of the implant) comprisingat least one withdrawal stop (12) on the anchor, such as a flexible lug(12), that can be disengaged from a complementary withdrawal stop (212)of the implant or from a second cooperation stop surface (190) (forexample, through access to the free end of the lug via the anchor itselfand/or via the implant), which are described in this application, solvethe problem of withdrawing the anchor from the vertebra and implantdespite the presence of a withdrawal stop or latch (and eventuallydespite the encumbrance of the implants and of this type of fixation).These technical features for the disengagement (liberation) of thewithdrawal stop thus allow many embodiments of objects such as anchoringdevices and/or systems in which anchor (1) may, but need not, comprisesrib (11). The implants and instruments that may be associated withanchors without rib (11) need not comprise grooves (211, 3011). Someobjects concerned may be implants comprising a recess (240) for accessto the withdrawal stop (12) of anchor (1). Various objects may alsoconcern anchors having a straight body or having a curved body. Theseparticular objects (i.e., any of these embodiments allowing to disengagethe withdrawal stop (12) of the anchor) may or may not also comprise anytechnical feature (or combination of technical features) described forany element (or combination of elements) of any object (or combinationof objects) disclosed in this application, as long as they are notincompatible, in particular because the structural adaptations that maybe required by such isolation or combination of features are directlyderivable from the appreciation of the present disclosure.

Intervertebral implants (2) comprising at least one passage (21)designed to receive anchoring device (1), such as a slit crossing aportion of the implant, a conduit, or another type of channel arrangedto receive anchoring device (1), are also within the scope of theinvention. Preferably, such implants are configured to receive at leastone anchoring device (1) comprising at least one curved and rigid plate,so as to allow the passage of this anchoring device (1) through thepassage (21) without deformation despite the curvature of the device(1). In most configurations, passage (21) crosses implant (2) from aperipheral wall (28) to an upper or lower surface of implant (2), alonga preferably rectilinear and oblique trajectory suited to the curvatureof anchoring device (1) and the desired fixation of the implant, asdiscussed in detail elsewhere in this disclosure. In someconfigurations, passage (21) in the implant comprises at least onegroove (211) of shape and size arranged for receiving a rib (or ribs)(11) of anchoring device (1), as explained elsewhere herein. The presentapplication does not describe intervertebral discs in detail, but ratheronly describes various embodiments of intersomatic cages designed for anarthrodesis. The person skilled in the art will nevertheless understandafter appreciating this disclosure that anchoring device (1) configuredwith various features and various combinations of features according tothe invention may be used with a prosthesis comprising at least oneperipheral wall to receive anchor (1) as described herein. For example,intervertebral prostheses are known whose vertebral contact plates havea sufficient height to offer a peripheral wall in which it is possibleto create a passage such as described herein for the insertion of theanchoring device. Likewise, intervertebral prostheses are knowncomprising two plates and a mobile core between the plates and in whicha peripheral wall of one of the plates limits the movements of the core.Therefore, the invention can be adapted to this type of prosthesis, bymaking at least one passage (21) in the wall, crossing said wall from aperipheral surface to a vertebral contact surface (lower or upper) ofthe plate without hindering the movements of the various parts of theprostheses, such as the core, for example. In various embodiments, thepassage (21) in the plate need not cross the plate from a peripheralwall of the plate, but instead may cross the plate from one side to theother side (i.e., the upper surface to the lower surface, or viceversa), according an oblique axis (straight or curved) extending from aperipheral area of the prosthesis itself to a vertebral endplate, andthe stops (14) and/or flexible tabs (12) of anchor (1) can be adapted tomake contact with the upper or lower surfaces of the plates (directly orvia stops arranged within the plate). For example, publications FR2,879,436, WO 2006/120505 and US 2006/0136063, each of which isincorporated herein by reference (filed by the assignee of thisapplication), show a straight anchor with a retaining stop formed by acurved portion (hook-shaped) at the posterior end of the anchorconfigured to engage a stem near the edges of plates, and this generalapproach can be adapted to the embodiments disclosed herein after fullyappreciating this disclosure. The anchor (1) of the present inventionmay, for example, be curved and/or comprise one or more ribs (11) and/orone or more retaining stops (14) and/or one or more withdrawal stops(12), for use with such prostheses, and additional features and/orcombinations of features described herein may be adapted to such use. Incases where the anchor is designed to cross through a plate of aprosthesis, the term “peripheral wall” may be used to designate aportion near the periphery of the plate and accessible from a peripheralarea of the prosthesis.

Accordingly, certain embodiments of the present invention also concernan intervertebral disc prosthesis created with the means describedgenerally for implant (2). Various types of intervertebral discprostheses are known and no detail will be given here, except that itmay for example comprises at least two plates articulated together (forexample via articulation surfaces of the plates and/or an intermediatecore) and at least one of which comprises at least one passage (21), forexample provided with at least one groove (211) when the anchorcomprises a rib (11). Intersomatic cages configured in accordance withthe present invention also can have various forms, includingconfigurations notably different from the illustrative examplesrepresented in the figures of the present application. The descriptionherein gives several non-limiting variants of embodiment in reference tothe attached figures, but after fully appreciating this disclosure itwill be understood that the cages and/or prostheses devised inaccordance with the present invention may have other forms withoutdeparting from the spirit and scope of the invention. Thus, in thepresent application, reference is made generally to an intervertebralimplant to designate both cages and prostheses, and also osteosynthesisplates. When particular embodiments of intersomatic cages requirereference to specific technical features of cages, however, referencemay be made to an intersomatic cage rather than to an intervertebralimplant.

Various intervertebral implants (2) described herein comprise at leastone peripheral wall (28), a posterior portion of which (in accordancewith the conventions adopted in this description) comprises at least onepassage (21) of suitable dimensions to receive at least one anchoringdevice (1) configured according to the invention. As explained elsewhereherein, the passage is may be straight to avoid the complex andexpensive machining of a curved passage. However, with an implantseparable into two parts at the passage joinable together, it is easierto create a curved passage. Moreover, it is possible to manufactureimplants, such as intersomatic cages, by moulding. It is then possibleto more easily produce implants having a curved passage, for example byusing a mold with a curved insert. In addition, certain recenttechniques allow curved machining, especially in solid materials (forexample metals). Therefore it is possible, particularly in the case ofintervertebral disc prostheses whose plates are made of metal, to createa curved passage designed to receive the curved anchor without muchadditional expense and burden over machining a straight passage. Ifpassage (21) in the implant is curved, its height can be generally equalto (or very slightly greater than) the thickness of anchor plate (10).If passage (21) is rectilinear (straight), its height preferably will beat least slightly greater than the thickness of the curved anchor topermit it to pass without deformation of anchor (1) despite itscurvature and its rigidity, as discussed elsewhere in the presentapplication. This technical feature of a curved passage (21) within theimplant allows many embodiments of objects such as implants andanchoring devices and/or systems in which the implant comprise a curvedpassage and in which the anchor is curved and may, but need not,comprise at least one rib (11). The implants and instruments which maybe associated with anchors configured without a rib need not comprise agroove (211, 3011). These particular objects (i.e., any of theseembodiments comprising or associated with a curved passage in theimplant) may be configured to solve the problems of facilitating theguidance of anchor and fixation of implant (which may be linked to theproblem of the stability of the anchor). In particular because thestructural adaptations that may be required by such isolation orcombination of features are directly derivable from the appreciation ofthe present disclosure, these particular objects may or may not alsocomprise any technical feature (or combination of technical features)described for any element (or combination of elements) of any object (orcombination of objects) disclosed in this application, as long as theyare not incompatible (such as for example a rigid anchor having astraight body is incompatible with such a curved passage).

In some embodiments, passage (21) in implant (2) as discussed elsewhereherein may comprise at least one groove (211) of complementary shape andsize to at least one rib (11) disposed on the anchor. However, anchors(1) having no rib (11) are possible.

In some embodiments (not shown), passage (21) may have an entrance withan oblique orientation, in which the width of the passage is neitheroriented parallel to the plane of the disc space, nor oriented parallelto the axis of the spine, but intermediate and forming an angle withthese reference orientations (which are shown in most of the figures).In these embodiments, it is preferable to have two anchors (1) implantedin the same vertebra, and these anchors (1) preferably have a curvaturein the thickness of the plate and one or more radius (or radii) ofcurvature shorter than generally used for anchors which may beassociated with implants having an entrance of the passage orientedvertically or horizontally, so that the anchor has a curvaturesufficient to provide a good hold despite its oblique orientation. Thisoblique orientation may be useful in various circumstances to addressthe problem of the stability of the anchor and the implant when facedwith various constraints of the implantation. Some embodiments mayprovide, for example, two such anchors associated with an implantcomprising at least two passages with such oblique orientation directedtoward the same vertebra, but with opposite orientation one in relationto other (for example, one entrance inclined 45° to the right, and theother inclined 45° to the left). These various embodiments may not needa rib (11) on the anchor (1), nor a groove (211) in the passage (21) ofthe implant (2) (nor groove (3011) in the instrument). These particularobjects (i.e., any of these embodiments comprising or associated with atleast one passage (21) which entrance has an oblique orientation) may ormay not also comprise any technical feature (or combination of technicalfeatures) described for any element (or combination of elements) of anyobject (or combination of objects) disclosed in this application, aslong as they are not incompatible, in particular because the structuraladaptations that may be required by such isolation or combination offeatures are directly derivable from the appreciation of the presentdisclosure.

The use of an anchor comprising a curved plate can be particularlyadvantageous with an osteosynthesis plate, in particular in the case ofthe disc space between vertebrae L5 and S1, because the orientation ofthe sacrum toward the back of the spine makes it generally difficult toaccess this area, even by an anterior approach. In general, even with acurved anchor (1), it is preferable to use an approach axis of theinstrumentation that is oblique (not perpendicular to the vertebrae) atthe level of the sacrum, because of the orientation of the latter towardthe back of the spine. The contact surface with the implant at theanterior end of the instrumentation may be inclined with respect to itslongitudinal axis (antero-posterior according to the convention used inthe present application) for allowing an optimal contact with theosteosynthesis plate. Nevertheless, the approach axis may besubstantially perpendicular to the osteosynthesis plate in somecircumstances and the instrumentation will then be adapted to thisapproach axis. Furthermore, it is also possible to use an anchorcomprising a straight plate, so as to allow this implantation in variouscircumstances (e.g., oblique path or path perpendicular to thevertebrae). The instrumentation will thus be adapted according to theshape of the anchor and the approach axis chosen. Implants devised withvarious features according to the invention may include osteosynthesisplates comprising a passage (21), with or without a groove (211)depending on whether the anchor (1) comprises a rib (11) or not. Theperipheral wall (28) then corresponds to osteosynthesis plate itself,forming a wall between the exterior and interior of the disc space. Theanchor is then inserted into the passage along an approach axissubstantially perpendicular to the osteosynthesis plate (and the axis ofthe spine at the level of the disc space concerned). The passages (21)in the plate can be arranged to be placed at the disc space or vertebralbody level and lead to the endplates or directly in the periphery of thevertebral bodies. The orientation of the entrances of the passages (21)may be oblique as explained above, especially if the anchor (1) does notcontain a rib (11). These fixation plates can be further fixed againstthe vertebrae with conventional screws, in addition to at least oneanchor as described herein.

It is noted that, in a general manner, passages, holes, notches, stops,recesses, lugs, and other elements of the various objects of theinvention (anchors, anchor systems, implants, and instruments) may beformed by various methods, such as machining, drilling, casting,welding, etc., and the examples given herein are not to be construedrestrictively.

As noted elsewhere herein, the anchor (1) may comprise at least one rib(11) on at least one part of at least one of its faces, and may compriseplural ribs (11) disposed on the same or opposite faces. Passage (21) ofthe implant for each anchor may therefore comprise several grooves(211), when needed to accommodate plural ribs on an anchor. An implantcan be fixed by means of several anchors, and it will therefore compriseseveral passages (21), each comprising one or more grooves if anchorswith one or more ribs (11) are to be used. Preferably, there will be twopassages (21) each oriented toward a different one of the vertebraebetween which the implant must be implanted. Thus, in certainembodiments, peripheral wall (28) comprises two passages (21) eachoriented toward one of the upper and lower surfaces of implant (2)(vertebral contact surfaces of the implant), so as to anchor anchoringdevice (1) in each of the vertebrae between which implant (2) isdesigned to be implanted. Passage (21) of an anchor (1) is created inwall (28) of the implant so as to emerge on the vertebrae contactsurface of the implant. In certain embodiments, peripheral wall (28) ofimplant (2) comprises two superposed passages (21) (FIGS. 2C, 2D, 3H,4B-H, 5C, 7A, 7B, and 8A-C) or offset passages (FIGS. 3B, 3E, 3K, 4A,5A, 5B, 13A, and 13D), each oriented toward one of the upper and lowersurfaces, so as to anchor anchoring device (1) in each of the vertebraebetween which implant (2) is designed to be implanted. In otherembodiments, implant (2) comprises only one passage (21). Embodiments ofprostheses similarly may have only one plate that comprises a passage(21), and the other plate does not.

Before anchoring device (1) is implanted to hold implant (2) inposition, there is sometimes a risk that implant (2) will move in thedisc space. In certain embodiments, therefore, at least one of the(upper and/or lower) vertebral contact surfaces of implant (2) maycomprises notches (25) preventing movement of implant (2) between thevertebrae. In the case of an intervertebral disc prosthesis, it is alsopossible to provide stabilization means on the surfaces designed to bein contact with the vertebrae, such as notches or fins or any type ofstructure preventing it from moving between vertebrae, so as to ensure(or improve) the stability of the prostheses before its fixation byanchoring device (1). According to different embodiments, these notches(25) or other stabilization means can have different orientations. Forexample, notches (25) can be substantially parallel to one another andall oriented perpendicular to the implant insertion axis, or notches(25) can, on the contrary, have different orientations on differentportions of implant (2), so as to prevent movement in variousdirections. As is particularly visible in the top views (FIGS. 2E, 5D,7C, 8G, 9D, 10D, 10E, 10F, 11C, 11D, 12A, 13B, 13E, 15A, 17A, 17B, and17C) of examples showing an intersomatic cage, the notches can bearranged substantially in a chevron pattern, relatively optimal foropposing movements in most directions, and, in particular, movementsperpendicular to the anteroposterior axis in these examples of cageswith lateral insertion (i.e., movements along an axis in a sagittal orpara-sagittal plane of the spine).

It is noted that in various figures of this application, examples ofcages represented include notches on almost their entire vertebralcontact surfaces, but not on the peripheral wall of the cage. Theposterior part of the vertebral contact surfaces of the cage has nonotches in these examples. However, it is possible in variousembodiments to provide notches on this and other peripheral parts,provided they do not interfere with the various stops, ribs, and/orother elements and features that may be configured on these implantsand/or the anchors that may be associated with them.

For a cage (e.g., 2A, 2B), peripheral wall (28) can define a cavity(26), opened on the upper and lower surfaces of the implant (those incontact with the vertebrae) designed to receive a bone tissue graft or asubstitute. Although an intersomatic cage can comprise a cavity (26) inits center defined by its wall (28), as shown in the figures of thepresent application, a cage may also consist of a solid piece without aninner cavity in other configurations within the scope of the invention.This type of cage can be designed to be used at least in pairs, forexample, so as to define a cavity between the cages such as is known inthe prior art. Moreover, in the case of cages with at least one cavity,and as particularly visible in certain examples shown in FIGS. 1, 2C,and 2, openings (24) can be created in wall (28) of the implant (thelateral walls in the examples shown), so as to also permit the growth ofbone tissue transversely through the disc space (i.e., through the cage,parallel to the vertebral endplates). In certain embodiments, not shown,the intersomatic cage may comprise a reinforcement crossing its cavity(26) from side to side to reinforce wall (28) of cage (2). Thisreinforcement can have different shapes and orientations and can beoriented along the axis of insertion of cage (2) between the vertebrae,for example, or along another axis. In various embodiments, thereinforcement can have a lower height than the rest of the cage. Thislower height of the reinforcement with respect to the rest of the cagepermits the cage to take on various possible irregularities in theshapes of the vertebral endplates. The reinforcement may or may not beprovided with notches (25). On the other hand, in certain embodiments, apart of passage (21) emerges into cavity (26). Generally, the wall canbe dimensioned as a function of passage (21), and passage (21) will bedimensioned and oriented as a function of anchoring device (1) in orderto orientate and hold this device in the direction of the vertebra intowhich the anchoring device must be affixed. Moreover, the orientationcan be chosen as a function of the desired fixation, as mentionedelsewhere herein (for example, by means of the curves selected for theanchors). Note, however, that the implant dimensions vary as a functionof the vertebrae between which they are designed to be implanted andthat the dimensions of the anchoring device can also be adapted to thoseof the implant as a function of those vertebrae.

The form of the implant, even at the level of passage (21), is notlimiting, as long as it allows at least one anchor (1) to be introduced.For example, cage (2) represented in the figures of the presentapplication and particularly visible in the top views (FIGS. 2E, 5D, 7C,8G, 9D, 10D, 10E, 10F, 11C, 11D, 12A, 13B, 13E, 15A, 17A, 17B, and 17C)has a substantially oblong periphery, except at passage (21) where thewall is substantially planar and near which it will be held by aninstrument (3, 4). Even in these examples, however, it is not necessarythat the wall be generally planar in this area, although it is generallypreferred. Note that in various illustrated intersomatic cages, thesubstantially oblong shape has a slight curve (especially visible in thetop views), but again, this shape is not restrictive with respect to thescope of the invention. Various top view figures, in particular FIGS.19A to 19H, show that various forms of intersomatic cages may have aperipheral wall (28) including a slightly concave (283) side face (orsurface), a slightly convex (284) side face (or surface), asubstantially flat (281) posterior face (or surface), and a curved front(282) face (or surface), but again, this shape is not restrictive withrespect to the scope of the invention. This “bean” shape, and especiallythe lateral (284) slightly convex side, substantially corresponding tothe anterior portion of various vertebrae (for cages with a lateralapproach axis), can support the edges of the endplates having a denserbone tissue. It is preferable that the shape of the implant be selectedaccording to the shape of vertebrae between which it will be implantedand to the axis of the anatomical pathway foreseen for its implantation.For some illustrated configurations, this curved shape is preferredbecause the cage is arranged for being inserted laterally (or by atrans-psoatic approach or by a retro-psoatic approach) and allows thecage to have a form offering the best stability once implanted in acoronal orientation (i.e., with its longitudinal axis in the coronalplane, also called front plane). As noted, the cage could have othershapes, preferably chosen for the expected use and insertion approach.For example, the cage may not be curved, notably in the case ofimplantation by an anterior approach, or may be even more curved,notably in the case of an implantation by the transforaminal route.

Generally, the shape of implant (2) can vary and the shape of the end ofinstrument (3, 4) that will be in contact with implant (2) canconsequently vary in various embodiments. Implant (2) can in fact havedifferent shapes, as long as it has at least one passage (21) suitablefor insertion of anchoring device (1) and preferably fastener (orattachment resources) (22) designed to cooperate with one end of animplantation instrument. Fastener (22) can, depending on the variousparticular embodiments, be associated with a particular shape of theimplant near this fastener (22) to provide good cooperation with theinstrument, or even have a particular shape cooperating with acomplementary shape of the instrument. For example, the instrument cancomprise a contact surface following the shape of the implant.

As previously mentioned, intersomatic cage (2) may or may not comprise acavity (26) in its center, particularly if several intersomatic cages(2) are to be implanted in a same intervertebral space. Cages thusimplanted are generally used to enclose bone tissue (graft) that willgrow inside the intervertebral space and allow fusion (arthrodesis) ofthe two vertebrae between which it is implanted. Using a substituteinstead of a bone graft is also known. In all cases, the purpose of cage(2) is to restore or maintain a space between the vertebrae. Before thegrowth of the graft and fusion of the vertebrae, cage (2) must remainproperly in place in the disc space, and various embodiments of thepresent invention facilitate its immobilization. Similarly, a prosthesistypically must be immobile in all cases.

In certain embodiments, at least one portion situated around the centerof the implant along the anteroposterior axis (which may correspond tolongitudinal axis L) is thicker than the rest of the implant, so as totake on the shape of the vertebrae. As seen for example in FIGS. 3A, 3D,3G, and 3J, the center of the implant may be thicker than its ends.Preferably, only the upper surface is convex since only the lowersurfaces of the vertebrae generally have a concavity.

In certain situations, notably depending on the vertebrae between whichimplant (2) must be implanted, it is desirable for implant (2) toimpose, accommodate, or correct lordosis, kyphosis, or even scoliosis,in addition to maintaining the space between the vertebrae. Certainembodiments therefore provide that the mean planes passing through theupper and lower surfaces of implant (2) (of the cage or at least one ofthe plates of the prosthesis) form an angle in at least one directionimposing, accommodating, or correcting lordosis, kyphosis, or scoliosiswith respect to the vertebrae between which implant (2) is implanted.This general approach is described, for example, in applications FR2,869,528 (and WO 2005/104996 and US 2005/0246024) and FR 2,879,436 (andWO 2006/120505 and US 2006/0136063), each of which is incorporatedherein by reference, in particular concerning the technical featuresallowing such inclination of the mean planes of the implants (i.e.,thanks to an angle between the mean planes of at least one plate orbetween the contact vertebral surfaces of a cage, and/or thanks to anasymmetric nucleus and/or to an offset position of the nucleus).Reference to the mean plane reflects herein that the (upper and lower)vertebral contact surfaces are not necessarily planar, since they can beprovided with notches or can be convex or even concave; therefore a meanplane is intended to reflect the general orientation that a vertebraresting on the surface will take. For example, several of theintersomatic cages (2) shown in the figures of the present applicationare lordosis-inducing cages—they are designed to be inserted laterallyand their portion intended to be positioned on the anterior side of thevertebrae is thicker than the opposite portion. In fact, as isparticularly visible in FIGS. 3B, 3E, 3H, and 3K, it is seen that thecage is thicker on the left than on the right. Note also that in theseFIG. 2, notches (25) are visible only on one of the lateral sides (theleft side) of the cages, since the cages are lordosis-inducing. Notchessituated on the side where the cage is thinner (the right) are present,but do not appear to project in the figure since only their upper end isvisible. Although certain embodiments have the mean planes passingthrough the upper and lower surfaces of implant (2) forming an angle,straight cages can be provided, which typically would thus besymmetrical and have the medial planes passing through the upper andlower surfaces of implant (2) configured substantially parallel to oneanother. Depending on the desired implantation route for the implant, anangle may be imposed in various directions. For kyphosis and lordosis,this direction is anteroposterior with regard to the spine, with eithera thinning of the implant toward the front of the spine to imposekyphosis, or a thinning of the implant toward the rear of the spine toimpose lordosis. To impose scoliosis, the mean planes passing throughthe upper and lower surfaces must form an angle along the otherdirection of the plane of the disc space (along a frontal or coronaldirection, i.e., along an axis oriented mediolaterally with respect tothe spine) with a thinning of the implant toward the right or the left,depending on the desired effect. For example, FIGS. 19B and 19Crepresent a cage for imposing lordosis and scoliosis: the front face(282) of the wall (28) of implant (2) is thinner than its back face(281), as particularly visible in FIG. 19B, and the concave side face(283) is thinner than the convex face (284), as particularly visible inFIG. 19C. In this example, the sides may not be curved, as mentionedelsewhere herein, and it should be noted that the various features ofthis cage (e.g., the location of passages 21) are configured withrespect to the specific insertion approach intended for this cage, whichmay change if a different approach is intended. As explained elsewhereherein, symmetrical implants may also be used, for example such as thecages of FIGS. 19E and 19G which side faces (283, 284) generally havethe same thickness (side to side). The symmetry of implants may concernthe back to front orientation and/or the side to side orientation. FIG.19F shows a no-lordosis and no-kyphosis cage, in which the two sides(283, 284) have the same thickness, but this cage does impose scoliosisbecause its front surface (282) is thinner than its back surface (281).Again, note that for the cage of FIG. 19F to address scoliosis, it wouldbe inserted through a lateral approach. The same applies to the exampleof the cage of FIG. 19H. It will be noted that the side faces (283, 284)of the cage of FIG. 19H are both concave, while the side faces (283,284) of the cage illustrated in FIG. 19F are both convex. Theseillustrative and not limiting examples show the variety of shapes andconfigurations of implants, within the scope of the invention, that maybe used depending on the application foreseen. For an inclination (e.g.,scoliosis, lordosis, kyphosis) of adjacent vertebrae, it generally maybe preferable for the width of the anchor to be oriented substantiallyperpendicular (or oblique, but not parallel) to the direction ofinclination to provide good resistance to movements and to the forcesexerted by the inclination. For example, for a cage for a scoliosisapplication (imposing a sideways inclination of the vertebrae),configured to be inserted by a lateral approach, an anchor (1) with acurvature of its plate (1) oriented in the depth of the plate will bepreferred (e.g., FIGS. 2G, 2H). Conversely, for a cage for alordosis/kyphosis application (imposing a back to front inclination ofthe vertebrae), configured to be inserted by a lateral approach, ananchor (1) with a curvature of its plate (1) oriented in the width ofthe plate will be preferred (e.g., FIG. 13G).

In certain embodiments, the peripheral wall (28) comprises, at the levelof an anterior part (using the direction conventions noted elsewhereherein), at least one beveled portion (27), for example, at least onechamfer on at least one peripheral portion of at least one of its upperand lower surfaces, so as to facilitate the insertion of implant (2)between the vertebrae. As is particularly visible in the example of theintersomatic cage of FIG. 1, the anterior end of the cage hassubstantially the shape of the point of a shell (bull-nose, mortar), tooptimize the penetration of the cage between the vertebrae, especiallywhen the space between said vertebrae is insufficient. Chamfer or bevel(27) may be present on both the lower and upper surfaces of implant (2).This chamfer (27) or beveled profile facilitates implanting implant (2)by conferring to it a somewhat lower height on its attack side (the onedesigned to be inserted first) than on the rest of the cage.

As explained in this disclosure, the various configurations orembodiments of implants (2) preferably will be adapted to theconfigurations or embodiments of anchors (1), in particular for theretaining stops (14) and/or the withdrawal stops (12). Thus, in certainembodiments, passage (21) comprises at least one stop (214) having atleast one stop surface generally facing the outside of implant (2),arranged for cooperating with at least one retaining stop (14) ofanchoring device (1) to hold the implant (2) once anchoring device (1)is fully anchored in a vertebra through passage (21). As mentionedelsewhere herein, for various configurations of the anchor, stop (214)may be situated either above and/or below the passage, to receive lugsprojecting above and/or below the anchor, or on the lateral sides ofpassage (21) so as to receive two projecting lugs on the sides of thebody of anchoring device (1), or any combination of these possibilities.Preferably, there will be 2 stops in each case. Preferably, stop (214)is a recess, the bottom of which forms the stop surface, with depthsufficient to receive retaining stop (14) without it protruding fromperipheral wall (28). In certain embodiments, the implant comprises atleast one withdrawal stop (212) having at least one stop surfacegenerally facing the anterior end of the anchoring device inserted inpassage (21), this withdrawal stop (212) cooperating with at least onewithdrawal stop (12) of anchor (1), such as a flexible lug (12), inorder to oppose the withdrawal of anchoring device (1) from implant (2).

In certain embodiments, an instrumentation (3, 4) may be used to insertimplant (2) between the vertebrae and to guide anchoring devices (1)into the implant (2) and drive the anchoring devices (1) into thevertebrae. In these embodiments, peripheral wall (28) of implants (2)preferably comprises at least one fastener (or attachment resources)(22) arranged for cooperating with a gripping end of an implantationinstrument (3, 4). Thus, various embodiments of potential objects of thepresent invention concern implantation instruments (3, 4) for theimplantation of intervertebral implants (2) and of anchoring device (1)to affix implant (2) against at least one vertebra. In variousembodiments, the instrument is adapted to anchoring device (1) in orderto affix this device in the vertebrae and also to intervertebralimplants (2) configured according to the invention, comprising at leastone fastener (22) (or attachment resources) for an implantationinstrument (3) so as to enable the implants (2) be gripped or held bythe instrument (3). In some configurations, the fastener of implant (2)may comprise at least one recess (22) as shown, for example, in FIGS.3B, 3E, 3H, 3K, 4(A to H), 5(A-B), 13A and 13D, designed to receive atleast one gripping resource (321) of the instrument. For example, anopening (22) can receive the end of a shaft (321) of an instrument.Opening (22) can be threaded to cooperate with a threading on the end ofshaft (321), as particularly visible in the examples of FIGS. 16A and16B, also showing other additional fasteners or attachment resources.However, the fastening means can also comprise a portion projectingoutside the implant designed to be inserted into a recess of a grippingmeans (not shown). In certain embodiments, fasteners or attachmentresources (22, 22 a, 22 b, 22 c) can also comprise arrangements formedat least in part by the different surfaces of the implant, with grippingresources of the instrument having a shape complementary to thesesurfaces to allow gripping the cage or prosthesis. For example, thefirst fastener may comprise an opening (22 a) in posterior wall (28) ofthe implant, receiving a shaft (321) of instrument (3), and may becomplemented by a recess (22 b) in one of the walls (lateral wall, forexample, in these figures) of implant (2), as particularly visible inFIGS. 2C, 2D, 5C, 8A-C, and 15F. As particularly visible in FIGS. 16B,16C and 17A, also showing another additional fastener, this recess (22b) is designed to receive a lug (3210) of a complementary shape ofinstrument (3). This double grip permits better holding implant (2)during implantation between the vertebrae and in particular, exertingtorsion on the implant, for example, by offering a lever arm betweengripping resources (22 a-321 and 22 b-3210). This double grip can alsobe improved by a third resources or arrangement (22 c), formed in thesecond resources or arrangement (22 b), as is particularly visible inFIGS. 1, 7A, 7B, 16B, 16C, and 17A. For example, the recess (orreinforcement) (22 b) in a wall of the implant can also comprise anotherrecess (a hole, a notch, etc.) designed to receive a complementary stud(3210 b) created on lug (3210) of the instrument (or a pin, lug, tab orany other projecting structure). In this example, as particularlyvisible in FIGS. 16B, 16C, and 17A, implant (2) is engaged by instrument(3) by inserting stud (3210 b) and lug (3210) into their respectiverecess (22 c and 22 b, respectively), then implant (2) is “locked” oninstrument (3) by means of shaft (321) which is mounted so as to slideon instrument (3) and can be tightened, if necessary. Thus, althoughimplant may comprise at least one complementary fastener (22) of atleast one gripping resources (321) of instrument (3), the grip may beimproved with one or more additional fastener (e.g., 22 a, 22 b, 22 c)complementary to each of gripping resources (321, 3210, and 3210 b,respectively) of the instrument. Note that the term “grip” should not beinterpreted in a limiting manner as referring only to a structure thatgenerally comprises two elements forming a gripping component, butrather its use in the present disclosure refers simply to the fact thatthat the indicated structure serves to hold the implant. Preferably,fastener (22) will be located near passage (21) to allow grippingimplant (2) by the instrument near the place where the anchoring deviceswill be inserted, so as to reduce the size of the assembly and toimprove the retention of the implant by the instrument, in particularwhen the anchors are implanted in the vertebrae, which generallyrequires tapping on the anchors (by means of impactor (4) describedbelow). Furthermore, as particularly visible in the figures showingvarious embodiments mentioned herein, the position of the fastener canvary as a function of the size of the posterior wall of the implant, theconfiguration of the anchors, and the size of the implant. Preferably,the configurations of the anchors, implants, and instruments areinterdependent and complementary.

Generally, an instrumentation (3, 4) for implanting intervertebralimplant (2) between vertebrae and implanting at least one anchoringdevice (1) in at least one of these vertebrae, configured in accordancewith the invention, preferably will comprise at least one impactor (4)comprising a head (44) of suitable shape and size to press anchoringdevice (1) and at least one guide (3) elongated along a longitudinalaxis extending between a gripping end for implant (2) and a pressingend. In various configurations, guide (3) comprises a head (30) ofsuitable shape and size to receive head (44) of the impactor at leastpartially and at least one guide surface (31). Preferably, becausecurved anchors are preferred, the guide surface (31) will have at leastone radius of curvature substantially identical to at least one radiusof curvature of an anchoring device (1), so as to guide this anchoringdevice (1) through passage (21) of implant (2), to impact anchoringdevice (1) into a vertebra (preferably into the vertebral endplate). Incertain embodiments, head (30) comprises at least one groove (3011)created for the passage of at least one rib (11) of anchoring device(1). Depending on the face or faces on which rib or ribs (11) are found,groove or grooves (3011) will be configured in guide (3) appropriatelyfor the passage of the rib (or ribs). In certain embodiments, groove(3011) created for passage of rib (11) of anchoring device (1) iscreated on at least a part of the upper wall and/or the lower wall ofcavity (300) of head (30) of guide (3).

Generally, in various configurations head (30) of guide (3) comprises acavity (300) of suitable shape and size to receive anchoring device (1)and at least partially receive head (44) of impactor (4), with guidesurface comprising at least two curved grooves (31, FIG. 17D) situatedoppositely on the sides of cavity (300) to receive and guide the lateralsides of anchoring device (1) on both sides of body (10), with head (44)of impactor (4) penetrating into cavity (300) from one end to the otherof these grooves (31).

In some configurations, the rib (11) of the anchor will help guide theimplant through head (30). A head (30) of the guide (3) comprising agroove (3011) for the passage of the rib (11) serves to guide the anchor(1) and generally will be preferred. The impactor is arranged to passinto the head (30) of the guide, and in some configurations the walls ofthe cavity (300) may be configured to guide the impactor.

Various configurations of the instrument allow a surgeon to load anchorsfor implantation even with the implant already mounted on the guide, andeven with the implant already implanted in an intervertebral space(wholly or partially). For example, the guide (3) can be configured forallowing the loading of anchor through the back of the head (30). Inaddition, the ability to load anchors through the back of the head (30)helps reduce crowding in the surgical opening. To reduce the size of thesurgical opening required, in various configurations of the instrumentpreferably the height of the head (30) is reduced as much as possible,while still providing an appropriate path for the insertion of theanchors into the implant. Preferably, the head will have a maximumheight approximating the height of the implant. If grooves (3011) arepresent in the head, a bit of additional height may be necessary, forexample as shown in FIG. 17D. Then, grooves (3011) extending to theexterior of the head (as shown in FIG. 17D, for example) may beparticular useful in such cases. In some embodiments, however, thecavity (300) is high enough to allow passage of the anchor (with or witha rib) without needing grooves (3011). Nevertheless, the use of grooves(3011) may be beneficial anyway, to provide enhanced guidance andstability of the anchor while it is being inserted into the implant andthe vertebra.

In configurations having the head (30) of the guide approximately thesame height as the implant or shorter, at least one stop may be providednear the anterior end of the guide. Such stop may, for example, beadjustable and/or fixed on the head or elsewhere on the body (tube,handle, head, etc.) of the guide (3), and prevent the guide frompenetrating too far into the disc space, especially during the impactionof the implant and/or the anchor (1).

In various configurations, the instrument comprises at least onegripping resource (321) designed to cooperate with at least one fastener(22) of implant (2). The presser end may, in some embodiments, comprisea handle (320) used for pressing the guide holding implant (2) to insertthe implant (2) into the intervertebral space. As is particularlyvisible in FIG. 16B, this handle can comprise a passage for shaft (321),which in this configuration is connected to a wheel (33) for screwinginto the implant (comprising a threaded hole as an attachment resource).The surgeon can tap on handle (320) and/or wheel (33), for example usinga hammer or by means of another tool of known type, to drive implant (2)between the vertebrae and into the intervertebral space. Upon fullyappreciating this disclosure, a person skilled in the art willunderstand that some of various elements and technical features ofinstrumentation (3, 4) can be present on or absent from theinstrumentation which may still be used with various embodiments ofimplants (2) or anchoring devices (1).

Guide (3) comprises an elongated body (32) allowing delivery of the cageto the intervertebral space without needing too much space. This guidebody (32) guides and/or houses shaft (321) that grips implant (2).Impactor (4) also comprises an elongated body (42), that can slide withrespect to body (32) of guide (3). This elongated body of impactor (4)can be formed by a shaft (42) sliding with respect to guide (3) when itis activated by handle (41). As is particularly visible in FIG. 16, thisimpactor body (42) can be guided in its slide along the guide by meansof a groove (324) created at the bottom of an opening (322) of handle(320) of guide (3). In certain embodiments, such as particularly visiblein FIG. 16B, wheel (33) of the guide is notched to allow passage of theimpactor body. In these embodiments, the wheel can be indexed, forexample by means of a ball (325) inserted into a recess and heldcompressed against wheel (33) by elastic resources (326) (such as aspring, for example), so that it can only be stopped in the positionswhere the notches of the wheel face groove (324) for guiding body (42)of impactor (4).

In certain embodiments, impactor (4) comprises a handle (41) that allowssliding impactor body (42) with respect to guide (3). This handle canalso be tapped on by the surgeon, for example with a hammer or by meansof another tool of a known type, to drive anchoring device (1) into avertebra through the implant. Moreover, in certain embodiments, impactor(4) comprises at least one stop (43) limiting the penetration of head(44) of impactor (4) inside head (30) of guide (3). In certain variants,this stop can be adjustable along body (42) of impactor (4) so as toallow adjusting the penetration of the impactor to the size of head (30)of guide (3) and the size of the anchoring device (1) used. In fact, forexample, as mentioned previously, the anchoring device (1) used can havea variable length depending on the clinical circumstances and guide head(30), and in particular curved guidance surface (31) will also have asize adapted to this length of anchoring device (1). Gripping resources(or arrangement) (321) holds implant (2) securely in place against guidehead (30), with the anterior end of guide surface (31) aligned with andopening into passage (21) of implant (2) and the posterior end of guidesurface (31) remaining accessible for insertion of anchoring device (1)for passage into the implant and then the vertebra. In certainembodiments, shaft (321) comprises a threaded end cooperating with acomplementary threading of recess (22, 22 a) to affix implant (2) whenthe shaft is activated by the guide handle or wheel (33). In certainembodiments, fastener (22) comprises a recess (22, 22 a) and grippingresources (321) comprises an end of a shaft sliding in a body (32) ofguide (3) when it is activated by a handle or wheel (33) to enter andleave recess (22, 22 a) of implant (2). As already mentioned, in certainembodiments, fastener (22) may comprise recess (22 a) and a groove (22b) on a lateral side of peripheral wall (28), with gripping resources(321) comprising one end of a shaft sliding in a body (32) of guide (3)when it is activated by a handle or dial (33) in order to enter andleave recess (22, 22 a) of implant (2), and a lug (3210) arranged to beengaged in groove (22 b) and serving as a lever arm for positioningimplant (2) between the vertebrae. Moreover, in certain variants, groove(22 b) comprises a recess (22 c) designed to receive a stud (3210 b) oflug (3210) so as to improve the grip of implant (2) by the instrument.

In certain embodiments, cavity (300) of head (30) comprises two guideelements (particularly visible in FIG. 17D), each comprising guidinggrooves (31) and each situated on a side of cavity (300). In thisexample, the guide elements are joined with head (30) by inserting theminside cavity (300), which can comprise fastening resources forimmobilizing these guide elements (310), such as pins, screws, clipsand/or other fastening items. In other examples, head (30) may be madewith integrally with guide grooves (31) directly inside cavity (300). Inthis case, the head may be made of two parts joined together, tofacilitate machining curved grooves (31). However, machining curvedguide surfaces (31) directly in the head is possible.

Other potential objects of the present invention concern an adapter (5,FIG. 20A-B) arranged for loading at least one anchor (1) in the head(30) of the guide (3). This adapter (5) is preferably arranged forholding at least one anchor (1) in an appropriate manner for theinsertion of this anchor (1) in the head (30) of the guide (3). Invarious embodiments, this adapter (5) is hollow and open at its anteriorand posterior ends (again according to the convention used in thepresent application), thus delimiting a cavity (50) open from end toend, forming a sort of conduit or channel (for example with a bodysubstantially of a shape of a hollow rectangular parallelepiped open atits ends). In various embodiments, this cavity (50) is of shape anddimensions substantially identical (or at least close or similar) tothose of the cavity (300) of the guide. Thus, the adapter (5) may bemounted on the impactor (4) which can pass through the cavity (50)therein. In some embodiments, for example, so that the adapter (5) holdson the impactor (4), the adapter (5) may be arranged so that the passingof the impactor (4) cause a slight deformation of the adapter (5) byconfiguring the initial dimensions of the inside of the cavity (50) ofthe adapter (5) to be slightly smaller than the size of the impactor (4)(and eventually also to those of the cavity of the guide), at least atthe level of its posterior end (according to the convention used in thepresent application). The external dimensions of the adapter (5) willpreferably be slightly larger than those of the cavity (300) of theguide (3), at least at the level of its posterior end (according to theconvention used in the present application), so that it doesn'tpenetrate within this cavity (300) of the guide (3). For example, thewall (51) of the adapter (5) may be configured with at least one slit(52) facilitating its deformation. Furthermore, the material of theadapter may be arranged for allowing such deformation. In variousembodiments, for example, the posterior end will be configured withinthe cavity (50) of the adapter (5), with at least one thickened (raised)portion (as a boss or a protruding part) for facilitating the holding ofthe adapter (5) on the impactor (4) and thus obtain dimensions of theentrance of the cavity (50) of the adapter that are slightly smallerthan those of the impactor (4). Such a thickened portion may be combinedwith a slit and/or a deformable material of the adapter (5) forfacilitating the passage of the impactor. The adapter (5) holding atleast one anchor (1) may thus be mounted on the impactor (4) which isused to bring the anchor at the entrance of the cavity (300) of theguide's head, thanks to the arrangement of the impactor (4) and theguide (3) (the impactor being disengageable from the guide, for examplevia the opening (322) of the handle (320) of the guide), and then forpushing the anchor (1) within the head of the guide, while leaving theadapter (5) at the entrance of the cavity (300) of the guide (3).Furthermore, in various embodiments, the lateral sides of the cavity(50) of the adapter (5) comprise at least one groove (preferably atleast one groove on each side, extending through at least one wall ofthe adapter or not, and straight or curved, according to the anchorused) arranged for holding and/or guiding at least one anchor (1), in amanner similar to the grooves (3011) of the guide (3), but preferablyonly on a (anterior) portion of the adapter. These grooves (53) of theadapter (5) are preferably arranged so that, when the impactor (4),cooperating with the body of the guide, brings at least one anchor (1)held by the adapter (5) to the head (30) of the guide (3), the anteriorend of the anchor (1) is substantially facing the entrance of thegrooves (3011) in the head (30) of the guide (3), such that the anchor(1) can penetrate in an adequate manner inside the guide (3). Thegrooves (53) of the adapter (5) are thus preferably a prolongation ofgrooves (3011) (i.e., either a prolongation of at least one archdescribed by these grooves (3011) of the guide (3), or a prolongation ofthe straight path of these grooves (3011) of the guide (3), according tothe type of anchor used). It is noted that this type of adapter (5) maybe particularly advantageous in certain embodiments in which two anchors(1) can't be inserted at the same time in the instrument, such as forexample in the cases where the anchors (1) are curved along the depth ofthe plate (10) (anchors with horizontal orientation) and where the head(40) of the impactor (4) has dimensions such that it substantially fillsthe cavity (300) of the guide (3) and thus would push both anchors (1)at the same time, these two anchors (1) thus interfering each otherinside the head (30) of the guide (3). Thus, in these cases, it ispossible to introduce a first anchor (1) in the guide (3) holding theimplant (2), to implant this implant (2) using the guide (3), and thento impact this anchor (1) in a vertebra using the impactor (4), and thento withdraw the impactor (4) for providing it with the adapter (5)holding a second anchor (1) and to insert the anchor (1) in the guide(3) and then to impact this anchor (1) in a vertebra using the impactor(4). It is noted that, conversely, in other embodiments, notably whenthe anchors (1) are curved along the width of the plate (anchors withvertical orientation), two anchors (1) don't interfere with each otherin the head (30) of the guide (3) because their path don't cross eachother. In these embodiments, such an adapter (5) may not be need, butmay nevertheless be used. In these cases of anchors (1) with verticalorientation, the grooves (53) of the adapter (5) will be on the inferiorand superior sides of the cavity (50) of the adapter (5) instead of thelateral sides. This type of adapter (5) allows the surgeon to introducethe anchor(s) later, if he wishes, rather than inserting the anchor(s)in the guide (3) when implanting the implant (2). Furthermore, incertain embodiments of the impactor (4), particularly corresponding tothe cases where the anchors (1) are curved along the width of the plate(anchors with vertical orientation), the width of the impactor (4) maybe configured to be only substantially half the width of the cavity(300) of the guide (3), so that the impactor (4) allows impacting onlyone anchor (1) at a time, instead of pushing both anchors (1) at thesame time as when the width of the impactor (4) is substantially thesame as the width of the cavity (300) of the guide (3). Thus, such animpactor (4) may be used for impacting a first anchor (1), and then forbeing turned so as to impact a second anchor (1). These variousembodiments of adapters (5), anchors (1) and impactors (4) thus allowthe implementation of various steps of methods for preparing theimplantation and of method for implantation, according to the sequencesdescribed above for example.

Other potential objects of the present invention relate to variousembodiments of methods of preparing for an implantation of, and/ormethods for implanting, intervertebral implant (2) into anintervertebral space and for preparing the fixation of, and/or forfixing, the implant to at least one vertebra. These methods may comprisea step of assembling the implant (2) onto a guide (3), a step of placingthe impactor (4) relative to the guide, a step of placing at least oneanchor (1) in the guide (3). These various steps can be implemented indifferent orders, thanks to the arrangement of various objects of theinvention, as described in various embodiments discussed in the presentapplication.

In various embodiments, these methods for preparing the implantation maycomprise:

-   -   providing an anchoring device (1) in accordance with an        embodiment discussed in this present application;    -   providing an spinal implant (2) in accordance with an embodiment        discussed in this present application;    -   providing an implantation instrument (3, 4) in accordance with        an embodiment discussed in this present application;    -   gripping the spinal implant (2) with the implantation instrument        (3, 4);

In various embodiments, these methods for preparing the implantation mayfurther comprise a step of introducing at least one anchoring device (1)within the instrument (3, 4).

In various embodiments, these methods for implanting a spinal implant(i.e., for inserting the implant within a disc space or onto vertebrae)may comprise the steps of the methods for preparing the implantation andmay further comprise:

-   -   inserting the spinal implant (2) in an intervertebral space        between adjacent vertebrae of a spinal column (or onto adjacent        vertebrae of a spinal column in the case of an osteosynthesis        plate);    -   presenting the anchoring device (1) along an approach axis that        is substantially perpendicular to the axis of the spine (at the        level of the adjacent vertebrae);    -   using the impactor (4) of the implantation instrument (3, 4),        inserting the anchoring device (1) through the guide head (30)        of the implantation instrument (3, 4) and through the passage        (21) in the implant (2), with the anchoring device (1)        traversing at least a portion of the implant (2); and    -   using the impactor (4) of the implantation instrument (3, 4),        implanting at least part of the anchoring device (1) in one of        the adjacent vertebrae and fully inserting the anchoring device        (1) in the implant (2).

In various embodiments of these methods for implanting a spinal implant,the step of fully inserting the anchoring device (1) in the implant (2)comprises abutting the retaining stop (14) of the anchoring device (1)against its complementary stop (214) within the implant (2).

Some embodiments of the methods for implantation of the presentinvention provide insertion of an implant along a lateral approach(i.e., along a trans-psoatic path, or along a retro-psoatic path). Thetrans-psoatic approach uses a path through the psoas, a muscle lateralto the spine. The retro-psoatic path uses a path behind the psoas, bypushing the psoas to the front of the patient. In various embodiments ofthese methods for implanting a spinal implant, the step(s) of insertingthe implant may thus comprise at least one step of cutting the psoas anda step of passing through the psoas. In various embodiments of thesemethods for implanting a spinal implant, the step(s) of inserting theimplant may thus comprise at least one step of pushing the psoas and astep of passing behind the psoas. It will be noted that, depending onthe case, the surgeon may also pass in front of the psoas.

Most technical problems solved by various technical features describedin the present application may be related to the problem of stabilitymentioned in the preamble of this present disclosure. After appreciatingthis disclosure, a person of skill in the art may design variousembodiments combining the following technical features, which arediscussed below, in a non limitative manner, in relation to at least oneof the problems mentioned in this application.

Each of these technical features or of these elements, described in atleast one embodiment or configuration and discussed below, may beisolated from other technical features of the object concerned by (orthe objects concerned by and/or associated with) said embodiment orconfiguration (and thus concerning the same or another element) and/ormay be combined with any other technical feature described herein, invarious embodiments or configurations, unless explicitly statedotherwise, or unless these features are incompatible and/or theircombination is not functional, in particular because the structuraladaptations that may be required by such isolation or combination offeatures are directly derivable from the appreciation of the presentdisclosure.

-   -   Stability of the anchor in the vertebrae and/or in the implant        (and thus possibly the stability of the implant between the        vertebrae):

Technical Features and Elements:

-   -   Rib (11): may be configured to stabilize the anchor in the        vertebrae, but also may be configured to stabilize the anchor in        the implant (including the groove (211) of the implant), which        may further stabilize the implant.    -   thickened portions and/or plane surfaces (20, 110: 110 a and/or        110 b, 111) in the case of a curved anchor in a straight        passage: may provide a snug fit of the anchor in the implant to        help stabilize the anchor in the implant and may therefore        stabilize the anchor in the vertebra, and therefore may further        stabilize the implant.    -   Anchors “vertically oriented”, i.e., curved in the direction of        the width of the plate (10): may be configured to stabilize        anchor in the vertebrae and thus may further stabilize the        implant.    -   Locking anchor in the implant: also improves the stability of        anchor in the implant and/or stability of the implant between        the vertebrae (and/or stability of the anchor in the vertebra)

Technical Features and Elements:

-   -   Retaining stop (14): may retain the implant pressed against the        vertebra thanks to the anchor planted in a vertebra. This        stabilizes the implant on the vertebra but also may further        stabilize the anchor in the implant and/or the vertebra.    -   Withdrawal stop (12): may retain/hold the anchor in the implant.        This stabilizes the anchor in the implant and/or the vertebra        and may further stabilize the implant between the vertebrae.    -   Cooperation Stops (18, 19): allow interlocking of 2 anchors in        the implant. This stabilizes the anchor in the implant and/or        the vertebra and may further stabilize the implant between the        vertebrae. These Cooperation Stops (18, 19) further allow        minimizing the necessary locking structures (and their size).    -   Removal of the anchor allows the intentional withdrawal of the        anchor (and possibly the implant). This problem may be related        to the stability of the implant (e.g., if it is not good). For        example, the surgeon may reposition the implant for better        stability:

Technical Features and Elements:

-   -   Retaining stop (14) accessible for intentional withdrawal:        -   Complementary Stop (214) in the implant may be arranged to            help pull on the retaining stop (14) of the anchor        -   Housing (240) in the implant may be arranged for providing            access to the retaining stop (14)    -   Cooperation Stops (18, 19) accessible for intentional        withdrawal:        -   Housing (40) in the anchor may be configured to provide            access to at least one of the cooperation stops (18, 19),        -   Housing (240) in the implant may be configured to provide            access to at least one of the cooperation stops (18, 19),    -   Withdrawal stop (12) accessible for intentional withdrawal:        -   Housing (40) in the anchor may be configured to provide            access to withdrawal stop (12),        -   Housing (240) in the implant may be configured to provide            for access to the withdrawal stop (12),        -   Housing (40) in the anchor may be configured to provide            access to at least one of the cooperation stops (18, 19)            and/or withdrawal stop (12)        -   Housing (240) in the implant may be configured to provide            for access to at least one of the cooperation stops (18, 19)            and/or withdrawal stop (12)    -   Guiding the anchor and fixing the implant facilitates the        implantation of the implant and anchor and facilitates obtaining        a good stability of the anchor in the vertebrae and/or implant        (and thus possibly the stability of the implant between the        vertebrae):

Technical Features and Elements:

-   -   A curved passage for a curved, rigid anchor helps guide the        anchor through the passage and may be configured for minimal        clearance of the anchor, which may provide a snug fit of the        anchor in the implant to help ensure good stability.    -   A straight passage for a straight, rigid anchor can be        configured to help guide the anchor through the passage, and        have minimal clearance of the anchor, which may provide a snug        fit of the anchor in the implant to help ensure good stability.    -   A straight passage for a curved, rigid anchor helps guide the        anchor through the passage and may be configured for minimal        clearance of the anchor, which may provide a snug fit of the        anchor in the implant to help ensure good stability.    -   A curved passage curve for a straight, rigid anchor or an anchor        with plural straight portions forming an angle between each        other: helps guide the anchor through the passage and may be        configured for minimal clearance of the anchor, which may        provide a snug fit of the anchor in the implant to help ensure        good stability.

Fixation of implant such as an osteosynthesis plate: The fixation of anosteosynthesis plate may be performed with a curved or straight anchor,along an approach axis preferably substantially perpendicular to theplate for the curved anchors or preferably substantially oblique withrespect to this plate for the straight anchors, which improves thestability of the osteosynthesis plate itself (implant fixed).Furthermore, when used in combination with an intersomatic cage, anosteosynthesis plate improves the immobility of the spine and thusfacilitates the stability of the cage. The plate-type implant improvesthe stability of a cage-type implant.

After fully appreciating this disclosure, a person skilled in the artwill understand that numerous embodiments and/or configurations invarious other specific forms are possible and within the scope of theinvention. Consequently, the present embodiments and/or configurationsshould be considered as non-limiting illustrative examples that may bemodified and still be within the scope of the attached claims, and theinvention should not be limited to the details provided above.

1. A device for anchoring an intervertebral implant to a vertebracomprising: a body comprising a rigid elongated plate extending betweena first end configured to penetrate into a vertebra and a second endconfigured for urging the device into a vertebra; and a connection foran anchor-extraction tool disposed along the body proximal to theposterior end.
 2. The device of claim 1 in which the connection is atleast one recess in the plate.
 3. The device of claim 1 in which theconnection is a bar disposed along the posterior end.
 4. The device ofclaim 1 in which the connection is comprised in a stop configured toretain the implant against a vertebra.
 5. The device of claim 1 in whichthe plate is flat.
 6. The device of claim 5 in which the plate comprisesan elongated rib extending from a surface of the plate along at least aportion of a length of the plate between the first end and the secondend.
 7. The device of claim 1 in which the plate comprises a first broadside, a second broad side, and two edges, and the plate is curvedbetween the first end and the second end with the first broad side beingconvex and the second broad side being concave.
 8. The device of claim 7in which the plate comprises an elongated rib extending from a surfaceof the plate along at least a portion of a length of the plate betweenthe first end and the second end.
 9. The device of claim 1 further inwhich the body further comprises a thickened portion configured forcontact with an inner wall of a passage in an intervertebral implant tostabilize the device when inserted fully in the intervertebral implant.10. An intervertebral implant configured for placement between an uppervertebra and a lower vertebra comprising: at least one peripheral wall;a passage in the peripheral wall configured to receive an anchorcomprising a rigid plate through an exterior opening of the passagedisposed along the peripheral wall and project the anchor toward theupper vertebra or the lower vertebra without deformation of the plate;and an access disposed along the peripheral wall configured toaccommodate an anchor-extraction tool for removal of an anchor insertedin the implant.
 11. The implant of claim 10 in which the passage isconfigured to receive an anchor comprising a flat plate.
 12. The implantof claim 10 in which the passage has a groove configured to receive arib disposed along a broad surface of the plate.
 13. The implant ofclaim 10 in which the passage is configured to receive an anchorcomprising a curved plate having a convex broad side and a concave broadside.
 14. The implant of claim 13 in which the passage has a grooveconfigured to receive a rib disposed along a broad surface of the plate.15. The implant of claim 10 further comprising a stop configured toengage a withdrawal stop of an anchor.
 16. A device for treatment of aspine comprising: an anchor comprising a body comprising a rigidelongated plate extending between a first end configured to penetrateinto a vertebra and a second end configured for urging the anchor into avertebra; and a connection for an anchor-extraction tool disposed alongthe body proximal to the posterior end; and an intervertebral implantcomprising at least one peripheral wall; a passage in the peripheralwall configured to receive the anchor through an exterior opening of thepassage disposed along the peripheral wall and project the anchor towardthe upper vertebra or the lower vertebra without deformation of theplate; and an access disposed along the peripheral wall configured toallow an anchor-extraction tool to reach the connection on the anchorwhen the anchor is fully inserted in the implant.
 17. The device ofclaim 16 in which the passage is straight and the plate is curved. 18.The device of claim 16 in which the anchor has a rib disposed along abroad side of the anchor and the passage has a groove configured toaccommodate the rib.
 19. The device of claim 16 in which the anchor hasa latch configured to inhibit withdrawal of the anchor from the implantafter full insertion of the anchor in the implant, and the implantprovides access to release the latch after full insertion of the anchorin the implant.
 20. The device of claim 16 in which the anchor bodycomprises a thickened portion configured for contact with an inner wallof the passage to stabilize the anchor in the implant.